ASP.NET with c# 10 Note: Answers might have been written by students in their own words. Examiners are requested to use their wisdom while correcting paper. 1. Attempt any two of the following: a Why exception handling is required? Write syntax for user define exception? Answer:( explanation 2 marks + syntax/example 3 marks) Exception handling: The mechanism of Exception Handling is throwing an exception and catching it C# uses try .... catch block. Code which may give rise to exceptions is enclosed in a try block, and catch block catches that exception and handles it appropriately. The try block is followed by one or more catch blocks. Example: Basic syntax: try { //programming logic(code which may give rise to exceptions) } catch (Exception e) { //message on exception } finally { // always executes } try: A try block identifies a block of code for which particular exceptions will be activated. It's followed by one or more catch blocks. catch: A program catches an exception with an exception handler at the place in a program where you want to handle the problem. The catch keyword indicates the catching of an exception. finally: The finally block is used to execute a given set of statements, whether an exception is thrown or not thrown. For example, if you open a file, it must be closed whether an exception is raised or not. Example: using System; class tryCatch { public static void Main() { int k=0; try { int n= 10/k; Console.WriteLine(”n=” + n); } catch(Exception e) { Console .WriteLine (“Division By zero exception”); } Console.WriteLtne(”Statement executed after Exception because of try catch”); } } Output: Division By zero exception Statement executed after Exception because of try catch b Explain inheritance and polymorphism. Answer: explanation(2 ½ marks each) Inheritance is the concept we use to build new classes using the existing class definitions. Through inheritance we can modify a class the way we want to create new objects. The original class is known as base or parent class & the modified class is known as derived or subclass or child class. The concept of inheritance facilitates the reusability of existing code & thus improves the integrity of programs & productivity of programmers. Polymorphism is the ability to take more than one form. For example, an operation may exhibit different behaviour in different situations. The behaviour depends upon the types of data used on the operation. Polymorphism is extensively used while implementing inheritance. Two types Operator polymorphism Function polymorphism c Short note on framework base class library. Answer: .NET supplies a library of base classes that we can use to implement applications quickly. We can use them by simply instantiating them & invoking their methods or by inheriting them through derived classes, thus extending their functionality. Much of the functionality in the base framework classes resides in the vast namespace called System. We can use the base classes in the system namespaces for many different tasks including: Input/Output Operations. String handling. Managing arrays, lists, maps etc. Accessing files & file systems. Accessing the registry. Security. Windowing. Windows messages. Database Management. Drawing. Managing errors & exceptions. Connecting to the Internet. d What is type casting? Explain the concept of Boxing and Unboxing. Answer(Type casting 1 mark + boxing 2 marks + unboxing 2 marks) Type casting: Type casting is a way to convert a variable from one data type to another data type. Boxing means the conversion of a value type on the stack to object type on the heap. The conversion from an object type back to a value type is known as unboxing. Boxing (value to reference) : When the compiler finds a value type where it needs a reference type, it creates an object ‘box’ into which it places the value of the value type. The following code illustrates this: int m=100; object om=m; //creates a box to hold m OR object om=(object)m; //C-style casting This code will create a temporary reference_type ‘box’ for the object on heap. Boxing operation creates a copy of the value of the m integer to the object om. Now both the variables m & om exist but the value of om resides on the heap. This means that the values are independent of each other. Consider following code: int m=10; object om=m; m=20; Console.WriteLine(m); //m=20 Console.WriteLine(om); //om=10 When a code changes the value of m ,the value of om is not affected. Unboxing : Unboxing is the process of converting the object type back to the value type. We can only unbox a variable that has previously been boxed. In contrast to boxing, unboxing is an explicit operation using C-style casting. int m=10; object om=m; //box m int n=(int)om; //unbox om back to an int When performing unboxing, C# checks that the value type we request is actually stored in the object under conversion. Only if it is, the value is unboxed. When unboxing a value, we have to ensure that the value is large enough to hold the value of the object. For ex. The code int m=500; object om=m; byte n=(byte)om; will produce a runtime error. 2. Attempt any two of the following: a Explain <LINK> tag with example. Answer:(use 1 mark + syntax 1 marks + 3 attributes-3 marks) Explanation: The <link> tag defines a link between a document and an external resource. The <link> tag is used to link to external style sheets. Syntax: <head> <link rel="stylesheet" type="text/css" href="theme.css"> </head Example: <link rel="stylesheet" type="text/css" href="default.css" /> 10 Where, rel-can be used to specify the relationship of the target of the link to the current page. type (content-type) type-This attribute Provides information about the content type of the destination resource, telling wether it's an HTML document, a JPG image, an Excel document, etc. href (uri)-The "href" attribute specifies the destination resource, which the element is linking to. It may specify a resource in the same website or in an external one. b What is Garbage Collector? How it works? Answer: Garbage Collector:(GC-2 marks+ working 2 marks+GC.Collect() 1 mark) In the common language runtime (CLR), the garbage collector serves as an automatic memory manager. It provides the following benefits: Enables you to develop your application without having to free memory. Allocates objects on the managed heap efficiently. Reclaims objects that are no longer being used, clears their memory, and keeps the memory available for future allocations. Managed objects automatically get clean content to start with, so their constructors do not have to initialize every data field. Provides memory safety by making sure that an object cannot use the content of another object. Working: A garbage collection has the following phases: A marking phase that finds and creates a list of all live objects. A relocating phase that updates the references to the objects that will be compacted. A compacting phase that reclaims the space occupied by the dead objects and compacts the surviving objects. The compacting phase moves objects that have survived a garbage collection toward the older end of the segment. GC.Collect() method: This method is used to call garbage collector explicitly. It is used to force a garbage collection to occur at any time. c What is CSS? Give its advantages and disadvantages. Answer:( CSS 1 mark + advantages 2 marks+disadvantages 2 marks) CSS: CSS stands for Cascading Style Sheets Cascading styles sheets (CSS) give Web designers more control over the formatting and display of their HTML documents. Styles define how to display HTML elements Advantages: • Style sheets save time in applying formatting or positioning to your Web pages by enabling you to script a few lines of code rather than extensive, redundant HTML code • You can apply and change formatting globally. • Style sheets allow more detailed control, such as line spacing, than HTML. • You will need to test your Web pages with multiple browsers in order to ensure compatibility when using style sheets. • To change the style of an element, you only have to make an edit in one place. • CSS has a much wider array of attributes than HTML. Disadvantages: • Cannot create layout • Browser compatibility – All browsers do not support CSS • CSS works differently on different browsers. IE and Opera supports CSS as different logic. d What is delegate? Explain the steps to implement delegate in C#.NET. Answer:(delegate def 1 mark + 1 mark each step) Delegate: The dictionary meaning of ‘Delegates’ is “A person acting for another person”. A delegate in C# is a class type object & is used to invoke a method that has been encapsulated into it at the time of its creation. Creating & using delegates involves 4 steps : Delegate declaration Syntax: modifier delegate return_type delegate_name(parameters) Delegate methods definition Syntax: modifier function_name(parameters) { //statement(s) } Note: signature of delegate and function must be same Delegate instantiation Syntax: new delegate_type(expression); Delegate invocation Syntax: Delegate_object(parameters); 3. Attempt any two of the following: a Explain CheckBox and RadioButton web server controls in ASP.NET . (use ½ mark each + syntax 1 marks each + imp properties 1 mark each) Answer: CheckBox: A check box displays a single option that the user can either check or uncheck and radio buttons present a group of options from which the user can select just one option. Basic syntax for check box: <asp:CheckBox ID= "chkoption" runat= "Server"></asp:CheckBox> CheckBox properties: AutoPostBack Specifies whether the form should be posted immediately after the Checked property has changed or not. Default is false CausesValidation Specifies if a page is validated when a Button control is clicked Checked Specifies whether the check box is checked or not id A unique id for the control runat Specifies that the control is a server control. Must be set to "server" Text The text next to the check box Event: 10 OnCheckedChanged The name of the function to be executed when the Checked property has changed RadioButton properties: Basic syntax for radio button: <asp:RadioButton ID= "rdboption" runat= "Server"> </asp: RadioButton> AutoPostBack A Boolean value that specifies whether the form should be posted immediately after the Checked property has changed or not. Default is false Checked A Boolean value that specifies whether the radio button is checked or not id A unique id for the control GroupName The name of the group to which this radio button belongs OnCheckedChanged The name of the function to be executed when the Checked property has changed runat Specifies that the control is a server control. Must be set to "server" Text The text next to the radio button b Explain the different parts that constitute ASP.NET application Answer: Content layout (aspx file), program logic(.cs file) and configuration file constitute an ASP.NET application(ex.global.asax or web.config). Content files Content files include static text, images and can include elements from database. Program logic Program logic files exist as DLL file on the server that responds to the user actions. Configuration file Configuration file offers various settings that determine how the application runs on the server c What is the difference between Button and LinkButton web server controls? Button Control: The Button control is used to display a push button. The push button may be a submit button or a command button. By default, this control is a submit button. A submit button does not have a command name and it posts the page back to the server when it is clicked. It is possible to write an event handler to control the actions performed when the submit button is clicked. A command button has a command name and allows you to create multiple Button controls on a page. It is possible to write an event handler to control the actions performed when the command button is clicked. Basic syntax: <asp:Button id="b1" Text="Submit" runat="server" /> LinkButton: The LinkButton and the ImageButton controls operate similarly to an ordinary Button control. presents itself as a simple <a> element but posts back (using JavaScript) instead of requesting a new page. Basic syntax: <asp:LinkButton Text="Click me" OnClick="lblClick" runat="server" /> d Write a code that shows how to write a "LOCAL" cookie to a client's computer. The "LOCAL" cookie, stores FirstName LastName Answer: (step1- Interface/layout 2 marks + step2 - code 3 marks) Step1: Create the user layout to enter FirstName and LastName. i.e. WebForm Step2: Code behind(.cs code) WriteCookieButton_Click event handler in the code behind file has the code required towrite the cookie to the client computer as shown below. protected void WriteCookieButton_Click(object sender, EventArgs e) { // Create an instance of HttpCookie class HttpCookie LocalCookie = new HttpCookie("LOCAL"); LocalCookie["FirstName"] = FirstNameTextBox.Text; LocalCookie["LastName"] = LastNameTextBox.Text; // Write the cookie to the client computer Response.Cookies.Add(LocalCookie); } Following is optional ReadCookieButton_Click event handler in the code behind may have code to read the cookiefrom the client computer as shown below. protected void ReadCookieButton_Click(object sender, EventArgs e) { // Check if the "LOCAL" cookie exists on the client computer if (Request.Cookies["LOCAL"] != null) { //Retrieve the "LOCAL" cookie into a cookie object HttpCookie LocalCookie = Request.Cookies["LOCAL"]; //Write FirstName,LastName and LastVisit values Response.Write("First Name = " + LocalCookie["FirstName"] + ""); Response.Write("Last Name = " + LocalCookie["LastName"] + ""); } } 4. Attempt any two of the following: a Explain CustomValidator control with suitable example. Answer: (explanation 1 mark + code example - 2 marks + properties 2 marks) CustomValidator control 10 The CustomValidator control allows you to write a method to handle the validation of the value entered. If the other validator controls don’t fulfill the requirements of the validation, the CustomValidator can be used. With the CustomValidator, both a client- and serverside validation function can be defined. Double click on the CustomValidator control and add the following code: protected void CustomValidator1:ServerValidate(object source, ServerValidateEventArgs args) { string str = args.Value; args.IsValid = false; //checking for input length greater than 6 and less than 25 characters if (str. Length < 7 II str. Length > 20) { return; } //checking for a atleast a single capital letter bool capital = false; foreach (char ch in str) { if (ch >= ‘A’ && ch <= ‘Z’) { capital true; break; } } if (!capital) { return; } bool digit = false; foreach (char ch in str) { if (ch >= ‘0’ && ch <= ‘9’) { digit = true; break; } if (!digit) { return; } args.IsValid = true; } } Important properties: Property Explanation ClientValidationFunction Specifies the name of the client-side validation script function to be executed. ControlToValidate The id of the control to validate ErrorMessage The text to display in the ValidationSummary control when validation fails. id: A unique id for the control IsValid: A Boolean value that indicates whether the control specified by ControlToValidate is determined to be valid OnServerValidate Specifies the name of the server-side validation script function to be executed Specifies that the control is a server control. Must be set to "server" runat b What is the relationship between master page and content page? Answer(explanation 1 mark each + syntax(tag) 1 ½ each) Every Master Page should include at least one ContentPlaceHolder control; this is a placeholder for the content from the content page. <asp:ContentPlaceHolder id=”ContentPlaceHolder1” runat=”server”> </asp : ContentPlaceHolder> The content page is a standard aspx page in which MasterPageFile attribute should be added to the page directive for binding the content page to the master page. The content pages can not include the common tags as <Body>, <Head> etc. You can design your content page just like any other aspx page by adding static text and server controls. <%@ Page Language = “C#” MasterPageFile = “.../master/MasterPage.master” AutoEventWireup = “true” CodeFile=”Default2.aspx.cs” Inherits=”Default2” Title=”Untitled Page” %> Inside the content pages by default Content server control is get added. While designing the, content page you have to add controls to the content server control For example, <asp: Content ID=”Content1” ContentPlaceHolderID=”ContentPlaceHolder1” Runat=”Server”> </asp : Content> The attribute ContentPlaceHolderlD is very important as it decides what content will be bound to which ContentPlaceHolder on the master page. It is way to decide the location of where the contents will be displayed. c Explain UrlEncode() and UrlDecode() methods in ASP.NET. Answer: We cannot send special characters through query string. All special characters should be encoded when you pass them through the query string. The encoded string must be decoded at the receiver. There are two methods to achieve this- UrlEncode and UrlDecode(): The main purpose of these two methods is to encode and decode the urls respectively. We need to encode the urls because some of the characters are not safe sending those across browser. Some characters are being misunderstood by the browser and that leads to data mismatch on the receiving end. Characters such as a question mark (?), ampersand (&), slash mark (/), and spaces might be truncated or corrupted by some browsers. UrlEncode() This method is used to encode a string to be passed through URL to a another web page. URLencode replaces unsafe ASCII characters with a "%" followed by two hexadecimal digits. Syntax: UrlEncode (string str ) UrlDecode() This method is used to decode the encoded URL string. Decodes any %## encoding in the given string. Syntax: UrlDecode (string str ) d Create a web page to read student’s seat number, name and contact number using text boxes. Use appropriate validation controls to validate the following Student roll number should be from 1 to 120, name is compulsory and contact number must be of 10 digits. Write HTML and code behind code. Answer:(Layout 2 marks+ Validation control properties 1 each) Following controls are required to use For seat number – RangeValidator Control Property ControlToValidate MinimumValue MaximumValue Error message Value txtSeatNo 1 120 Invalid seat no For name – RequiredFieldValidator Control Property Value ControlToValidate txtName Error message Name field is compulsory For contact number – RegularExpresionValidator Control Property Value ControlToValidate txtContactNo ValidationExpression \d{10} Error message Invalid contactnumber 5. Attempt any two of the following: a What is DataReader? Explain ExecuteReader, ExecuteNonQuery methods. Answer(explanation 1 mark+ExecureReader 2+ExecuteNonQuery 2) DataReader: DataReader is used to read the data from database and it is a read and forward only connection oriented architecture during fetch the data from database. Generally we will use ExecuteReader object to bind data to datareader. 1. ExecuteNonQuery: Executes commands that have no return values such UPDATE or DELETE. It returns an integer that indicates the number of rows that were affected. Example:. int result=cmd.ExcecuteNonQuery(); 2. ExecuteReader : Returns a result set by way of a DataReader object. It contains a record in memory at any time. It is used to retrieve a read-only, forward-only stream of data from database. Example: DataReader dr=null; dr=cmd.ExecureReader(); b Explain command object in ADO.NET Answer(explanation 1+properties and methods 2 each) Command object: The ADO Command object is used to execute a single query against a database. The query can perform actions like creating, adding, retrieving, deleting or updating records. If the query is used to retrieve data, the data will be returned as a RecordSet object. This means that the retrieved data can be manipulated by properties, collections, methods, and events of the Recordset object. 10 c Consider there is a table named StudentsInfo having fields such as CodeNo, Name, Address, ContactNo, City in Sql Server. Write code to display get all record from database into GridView control. Answer: SqlConnection conn = new SqlConnection(); conn.ConnectionString = (@"Data Source=ADMIN-PC\SQLEXPRESS;Initial Catalog=Database_Name;Integrated Security=True"); string query = "SELECT * FROM StudentsInfo "; try { conn.Open(); SqlCommand cmd = new SqlCommand(query, conn); SqlDataAdapter da = new SqlDataAdapter(); da.SelectCommand = cmd; DataSet myDS = new DataSet(); da.Fill(myDS,"Student"); GridView1.DataSource = myDS; GridView1.DataBind(); } catch (Exception ex) { lblMessage.Text = "Problem in connection or in database"; } finally { conn.Close(); } d Explain windows authentication in ASP.NET. Anser: Windows authentication: The Windows authentication provider is the default provider for ASP .NET. It authenticates the users based on the users Windows accounts. Windows authentication in ASP.NET actually relies on IIS to do the authentication. IIS be configured so that only users on a Windows domain can log in. if a user attempts access a page and is not authenticated then user will be shown a dialog box asking them to enter their username and password. This information is then passed to the Web server and checked against the list of users in the domain. if the user has supplied valid credentials access is granted. To configure ASP.NET to use Windows authentication use the following code: <system. web> <authentication mode=”Windows”/> <authorization> <allow users”*”/> </authorization> </system.web> <allow users=”*”/> statement specifies permissions are provided to authorized users as well anonymous users. There are four different kinds of Windows authentication options available that can configured in IIS and they are given bellow: • Anonymous Authentication: In this, IIS does not perform any authentication check and allows access to any user to the ASP .NET application. • Basic Authentication: In this, a Windows user name and password have to be provided to connect. This information is sent over the network in plain text and hence this is an insecure kind of authentication. • Digest Authentication: It is almost same as Basic Authentication but the password is hashed before it is sent across the network. •Integrated Windows Authentication: In this, password is not sent across the network and some protocols are used to authenticate users. It provides the tools for authentication and strong cryptography is used to help to secure information in systems across entire network. 6. Attempt any two of the following: a What is Ajax? Explain UpdatePanel control with example. Answer: Answer: 1. The Update Panel control is a key component in creating flicker-free pages. In its most basic application, you simply wrap the control around content you want to update, add a ScriptManager to the page, and you’re done. 2. Whenever one of the controls within the UpdatePanel causes a postback to the server, only the content within that UpdatePanel is refreshed. Protected void Page Load(Obj ect sender,Eventargs e) { Label 1 .text=System.DateTime.Now.ToStringQ; } <asp:UpdatePanel 1D=”Updatepanel” runat=”server”> 10 <ContentTemplate> <asp:TextBox ID=”Text1” runat= “server”></asp :TextBox> <asp:TextBox ID=”Text2” runat= “server”></asp :TextBox> <asp:Label ID=”Labell” runat= “server”></asp :Label> <asp :Button ID=”Button1” runat “server” text=”Calculate” /> </ContentTemplate> </asp :UpdatePanel> <asp:Content ID=”Content2” ContentPlaceHolderlD=”cpMainContent” runat=”Server”> <asp: S criptManager ID “ ScriptManagerl” runat “ server”> </asp :ScriptManager> <asp:UpdatePanel ID”UpdatePanel 1” runat=”server”> How It Works 1. By wrapping the content in an UpdatePanel you define a region in your page that you want to refresh without affecting the entire page. 2. In the example, the Button control inside the UpdatePanel caused a postback and thus a refresh ofjust the region the control is defined in. Rather than replacing the entire page, only the part of the page that is wrapped in the UpdatePanel is refreshed, causing a flicker-free reload of the page. 3. The UpdatePanel and its content is the only part of the page that is updated when you click a button.This is the default behavior of an UpdatePanel, where only its inner contents are refreshed by other server controls defined within the <Content Template> element. b What is the use of Document Ready function? Document.Ready: All You jQuery methods in our examples are inside a document ready event: $(document).ready(function(){ // jQuery methods go here... }); This is to prevent any jQuery code from running before the document is finished loading (is ready). It is good practice to wait for the document to be fully loaded and ready, before working with it. This also allows you to have your JavaScript code before the body of your document, in the head section. Here are some examples of actions that can fail if methods are run before the document is fully loaded: Trying to hide an element that is not created yet Trying to get the size of an image that is not loaded yet Tip: The jQuery team has also created an even shorter method for the document ready event: $(function(){ // jQuery methods go here... }); c Explain JQuery expression with example d Create a web page to declare and initialize array of 10 integers and display the numbers greater than 30 using LINQ. Code should execute on button's click event in a web page. Answer: Button1_Click() { // Data source. int[] numbers = { 90, 8,71, 82, 93, 75, 82 ,45,9,2}; // Query Expression. IEnumerable<int> searchQuery = //query variable from numbers in numbers //required where score > 30 // optional select numbers; //must end with select or group // Execute the query to produce the results foreach (int n in searchQuery) { Console.WriteLine(n); } } // Outputs: 90 71 82 93 75 45 7. Attempt any three of the following: a What is post-back event? Explain IsPostBack with suitable example. Answer(explanation 2 marks + example 3 marks) If Page.IsPostBack property is false, the page is loaded at a first time.If it is true, the page is posted back to the server i.e. loaded for the next time. The Page_Load() event runs every time the page is loaded but if you want to execute the code in the Page_Load event only once i.e. for the first time page is loaded then you can use Page.IsPostBack property. Example: <HEAD runat=”server”> <Script runat=”server”> protected void Page_Load(object sender, EventArgs e) { if(!IsPostBack) { Label1.Text=”Page is loaded first time” } else { Label1.Text=”Page is not loaded first time” } </Script> </HEAD> <BODY> <Form id=”form1” runat=”server”> <asp:Label id=”Label1” runat=”server” Text=” ”/> <asp :Button id=”Button1” runat “server” Text=”Submit” /> </Form> </BODY> b Write a code to achieve overriding using virtual method. Use comments whenever necessary. 15 Answer: class Base //base class { public virtual void Display() //virtual method in base class { System.Console.WriteLine("Display - Base"); } } class Derived : Base { public override void Display() //derived class base class Display() is overridden here { System.Console.WriteLine("Display - Derived "); } } class Demo { public static void Main() { Base b; b = new Base (); b.Display(); b = new Derived (); b.Display(); } } Output Display - Base Display - Derived c Explain the Provider Model of ASP .NET. Answer:(explanation 3 marks + diagram 2 marks) With the provider model the system is flexible to able to use any class that extends a particular base class. Users can create their own derived classes that include some custom logic and business rules. The new class can be flawlessly plugged into the system without troubling existing code of the application. Provider model provides clean separation between the code and the backend implementation. A provider is software that provides a standardized interface between a service and a data source. ASP.NET providers are as follows: 1. Membership 2. Role management 3. Site map 4. Profile 5. Session state etc. d Write short note on jQuery event functions. Answer:(syntax and explanation 3marks+JQuery method 2 marks) jQuery Event Methods/functions: Event methods trigger, or bind a function to an event for all matching elements. Trigger example: $("button").click() - triggers the click event for a button element. Binding example: $("button").click(function(){$("img").hide()}) - binds a function to the click event. All the different visitor's actions that a web page can respond to are called events. Event methods trigger or attach a function to an event handler for the selected elements. The following table lists all the jQuery methods used to handle events. bind() Attaches event handlers to elements blur() Attaches/Triggers the blur event change() Attaches/Triggers the change event click() Attaches/Triggers the click event dblclick() Attaches/Triggers the double click event focus() Attaches/Triggers the focus event hover() Attaches two event handlers to the hover event keydown() Attaches/Triggers the keydown event keypress() Attaches/Triggers the keypress event keyup() Attaches/Triggers the keyup event mousemove() Attaches/Triggers the mousemove event mouseout() Attaches/Triggers the mouseout event mouseover() Attaches/Triggers the mouseover event mouseup() Attaches/Triggers the mouseup event ready() Specifies a function to execute when the DOM is fully loaded unload() Deprecated in version 1.8. Attaches an event handler to the unload event e Differentiate between DataSet and DataReader. Answer: DataSet DataReader The DataSet class in ADO.Net operates DataReader is a connection oriented in an entirely disconnected nature. service. DataSet is an in-memory representation of a collection of Database objects including related tables, constraints, and relationships among the tables. It fetches entire table or tables at a time so greater network cost. DataSet is not read-only so we can do any transaction on them. DataAdapter is used to get data in DataSet DataReader is designed to retrieve a read-only, forward-only stream of data from data sources. It fetches one row at a time so very less network cos. DataReader is readonly so we can't do any transaction on them. DataAdapter is not required Dataset works with the help of xml technology Example: Dataset ds=new Dataset ( ); DataReader doesn’t provide this feature. Example: Sqlcommand cmd =new sqlcommand (select * from emptable); DataAdapter1Fill(ds,”newtablename”) // where newtablename is table alias name Data Reader dr= cmd.ExecuteReader ( in dataset ) f What are different ways to integrate a CSS into a web page? Answer: (i) Inline stylesheet: Style specifications are placed directly inside an HTML element in the code. Inline Styles cannot be reused at all. Example of an Inline Style: <p style="font-size: 14px; color: purple;"></p> The style is embedded inside the HTML element using the style attribute. The above style cannot be reused at all. It will only target that one paragraph. (ii) Embedded stylesheet(Internal stylesheet): In this type style specifications are placed within the head section of the web page inside style tag. Internal Styles are placed inside the head section of a particular web page via the style tag. Internal Styles are placed inside the <head> section of a particular web page via the style tag. <style type="text/css"></style> These Styles can be used only for the web page in which they are embedded. Therefore, you would need to create these styles over and over again for each web page you wish to style. When using the style builder in Expression Web, Define the style in the Current Page. This will create an Internal Style. Advanced Use of Internal Styles unless you need to override an External Style. Example Embedded stylesheet: <html> <head> <title>Learning HTML</title> <style type="text/css"></> p { color: blue; } .importantstuff { font-size: 20px; } #lookhere { font-size: 28px; text-align: center; color: green; } </style> </head> <body> <p>Woo hoo! I'm learning HTML!</p> <p class="importantstuff">Woo hoo! I'm learning HTML!</p> <p class="importantstuff" id="lookhere">Woo hoo! I'm learning HTML!</p> <p class="importantstuff">Woo hoo! I'm learning HTML!</p> </body> </html> (iii) External style sheet: External CSS is a that contains only css code and it is saved with .css extension. This css file is then referenced in your HTML using the <LINK> .tag in header section of a page. The scope of external css is an entire page. Syntax/example: <head> <link rel="stylesheet" type="text/css" href="mystylesheet.css"> </head>
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