ASP.NET Web Forms provides a rich set of server controls that enable developers to create dynamic and interactive web applications. These controls can be categorized into several types based on their functionality. Below are the main types of server controls available in ASP.NET Web Forms:

1. HTML Server Controls

HTML server controls are standard HTML elements that can be enhanced with server-side functionality. By adding the runat="server" attribute, these controls can be accessed and manipulated on the server side.


    <input type="text" id="txtName" runat="server" />
    <input type="button" value="Submit" runat="server" OnServerClick="btnSubmit_Click" />

Code-behind:


    protected void btnSubmit_Click(object sender, EventArgs e)
    {
        string name = txtName.Value;
        // Process the name
    }

2. Web Server Controls

Web server controls are built-in controls provided by ASP.NET that offer a higher level of abstraction and functionality. They include controls for data binding, user input, and more.

Common Web Server Controls:

  • TextBox: Used for user input.

    •         <asp:TextBox ID="txtName" runat="server" />
  • Button: Triggers server-side events.

    •         <asp:Button ID="btnSubmit" runat="server" Text="Submit" OnClick="btnSubmit_Click" />
  • Label: Displays text on the page.

    •         <asp:Label ID="lblMessage" runat="server" />
  • DropDownList: Allows users to select an item from a list.

    •         <asp:DropDownList ID="ddlOptions" runat="server">
                <asp:ListItem Text="Option 1" Value="1" />
                <asp:ListItem Text="Option 2" Value="2" />
            </asp:DropDownList>
  • GridView: Displays data in a tabular format.

    •         <asp:GridView ID="gvData" runat="server"></asp:GridView>

3. Data Controls

Data controls are specialized server controls that are used to display and manipulate data from various data sources. They include:

  • GridView: Displays data in a grid format and supports sorting, paging, and editing.
  • ListView: Provides a flexible way to display data using templates.
  • Repeater: A lightweight control for displaying repeated data.

4. Validation Controls

Validation controls are used to validate user input on the server side before processing it. Common validation controls include:

  • RequiredFieldValidator: Ensures that a field is not left empty.

    •         <asp:RequiredFieldValidator ID="rfvName" runat="server" ControlToValidate="txtName" 
                ErrorMessage="Name is required!" ForeColor="Red" />
  • RegularExpressionValidator: Validates input against a regular expression.
  • CompareValidator: Compares the value of two controls.

5. Login Controls

ASP.NET provides a set of login controls that simplify user authentication. These include:

  • Login: A control for user login.

    •     <asp:Login ID="Login1" runat="server" />
  • LoginStatus: Displays the login status of the user.
  • LoginName: Displays the name of the logged-in user.

Conclusion

ASP.NET Web Forms offers a variety of server controls that cater to different needs in web application development. Understanding these controls and their functionalities can significantly enhance the development process and improve user experience. By leveraging these controls, developers can create dynamic, interactive, and user-friendly web applications.