AttributeCollection.Item Property (String)


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Gets or sets a specified attribute value for a server control.

Namespace:   System.Web.UI
Assembly:  System.Web (in System.Web.dll)

public string this[
	string key
] { get; set; }


Type: System.String

The location of the attribute in the collection.

Property Value

Type: System.String

The attribute value.

You can add an attribute to or retrieve one from an ASP.NET server control that uses this property.

The following example shows how to set a dynamic HTML onblur attribute to run an ECMAScript (JavaScript) command when a TextBox Web server control loses focus.

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
<html xmlns="" >
<head runat="server">
    <title>Attributes Property of a Web Control</title>
<script language="c#" runat="server">

       void Page_Load(Object sender, EventArgs e) {
          TextBox1.Attributes["onblur"]="javascript:alert('Hello! Focus lost from text box!!');";    

   <h3>Attributes Property of a Web Control</h3>
<form id="form1" runat="server">

   <asp:TextBox id="TextBox1" columns="54" 
    Text="Click here and then tab out of this text box" 


.NET Framework
Available since 1.1
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