InitialValue Property
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RequiredFieldValidator.InitialValue Property

 

Gets or sets the initial value of the associated input control.

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

[ThemeableAttribute(false)]
public string InitialValue { get; set; }

Property Value

Type: System.String

A string that specifies the initial value of the associated input control. The default is String.Empty.

Use this property to specify the initial value of the input control.

Validation fails only if the value of the associated input control matches this InitialValue upon losing focus.

System_CAPS_noteNote

The strings in both the InitialValue property and the input control are trimmed to remove extra spaces before and after the string before validation is performed.

This property cannot be set by themes or style sheet themes. For more information, see ThemeableAttribute and ASP.NET Themes and Skins.

The following example demonstrates how to use the InitialValue property to ensure that the user enters a value in the text box.

System_CAPS_security Security Note

This example has a text box that accepts user input, which is a potential security threat. By default, ASP.NET Web pages validate that user input does not include script or HTML elements. For more information, see Script Exploits Overview.

<%@ Page Language="C#" AutoEventWireup="True" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
    <title>RequiredFieldValidator InitialValue Example</title>
</head>
<body>

   <form id="form1" runat="server">

      <h3>RequiredFieldValidator InitialValue Example</h3>

      Name: 
      <asp:TextBox id="Text1" 
           Text="Enter a value" 
           runat="server"/>

      <asp:RequiredFieldValidator id="RequiredFieldValidator1" 
           InitialValue="Enter a value" 
           ControlToValidate="Text1"
           ErrorMessage="Required field!"
           runat="server"/>

      <br />

      <asp:Button id="Button1"
           Text="Validate" 
           runat="server"/>

   </form>

</body>
</html>

The following example demonstrates how to use the InitialValue property to ensure that the user selects an item from the list box.

<%@ Page Language="C#" AutoEventWireup="True" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
    <title>RequiredFieldValidator InitialValue Example</title>
</head>
<body>

   <form id="form1" runat="server">

      <h3>RequiredFieldValidator InitialValue Example</h3>

      <asp:ListBox id="list"
           runat="server">

         <asp:ListItem Value="Australia">Australia</asp:ListItem>
         <asp:ListItem Selected="True" Value="NoCountry">--ChooseCountry--</asp:ListItem>
         <asp:ListItem Value="USA">USA</asp:ListItem>

      </asp:ListBox>

      <asp:RequiredFieldValidator id="valList"
           ForeColor="#FF0000"
           ErrorMessage="Selection Invalid!"
           ControlToValidate="list"
           InitialValue="NoCountry"
           EnableClientScript="False"
           runat="server"/>

      <br />

      <asp:Button id="Button1"
           Text="Submit"
           runat="server"/>

   </form>

</body>
</html>

.NET Framework
Available since 1.1
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