.NET Framework 类库
IValidator.IsValid 属性

当由类实现时，获取或设置一个值，通过该值指示用户在指定控件中输入的内容是否通过验证。

命名空间:System.Web.UI
程序集:System.Web（在 system.web.dll 中）

语法
Visual Basic（声明） 
Property IsValid As Boolean
Visual Basic（用法） 
Dim instance As IValidator
Dim value As Boolean

value = instance.IsValid

instance.IsValid = value
C# 
bool IsValid { get; set; }
C++ 
property bool IsValid {
    bool get ();
    void set (bool value);
}
J# 
/** @property */
boolean get_IsValid ()

/** @property */
void set_IsValid (boolean value)
JScript 
function get IsValid () : boolean

function set IsValid (value : boolean)

属性值

如果该内容有效，则为 true；否则为 false。
示例
Visual Basic 
<HTML>
   <HEAD>
      <script language="VB" runat="server">

         Sub Button_Click(sender As [Object], e As EventArgs)
            ' Generating a random number.
            Dim rand_number As New Random()
            myCompareValidate.ValueToCompare = rand_number.Next(1, 10).ToString()

            ' Set the ErrorMessage.
            myCompareValidate.ErrorMessage = "Try Again!!"
            myCompareValidate.Validate()

            ' Check for Validity of control.
            If myCompareValidate.IsValid And myTextBox.Text <> "" Then
               labelOutput.Text = "You guessed correctly!!"
               labelOutput.ForeColor = System.Drawing.Color.Blue
            Else
               labelOutput.Text = "You guessed poorly"
               labelOutput.ForeColor = System.Drawing.Color.Black
            End If

            labelOutput.Text += "<br><br>" + "The number is: " + _
               myCompareValidate.ValueToCompare
         End Sub 'Button_Click

  </Script>
</HEAD>
    <body>
       <form runat="server" ID="myForm">
          <h3>IValidator Example demonstrating IsValid & ErrorMessage</h3>
          <h5>Guess!! a number between 1 and 10:</h5>
          <asp:TextBox id="myTextBox" runat="server" />
          <asp:CompareValidator id="myCompareValidate"
               ControlToValidate="myTextBox" ValueToCompare="0"
               EnableClientScript="False" Type="Integer" Text="*"
               runat="server" />
          <br>
          <asp:Button Text="Submit" OnClick="Button_Click" runat="server" />
          <br>
          <asp:Label id="labelOutput" runat="server" />
          <br>
          <asp:ValidationSummary id="Summary1" runat="server" />
       </form>
    </body>
</HTML>
C# 
<HTML>
  <HEAD>
    <script language="C#" runat="server">

     void Button_Click(Object sender, EventArgs e)
     {
        // Generating the random number.
        Random rand_number = new Random();
        myCompareValidate.ValueToCompare = rand_number.Next(1, 10).ToString();

        // Setting the ErrorMessage.
        myCompareValidate.ErrorMessage="Try Again!!";
        myCompareValidate.Validate();

        // Check for Validity of control.
        if ((myCompareValidate.IsValid) && (myTextBox.Text != ""))
        {
           labelOutput.Text = "You guessed correctly!!";
           labelOutput.ForeColor = System.Drawing.Color.Blue;
        }
        else
        {
           labelOutput.Text =  "You guessed poorly";
           labelOutput.ForeColor = System.Drawing.Color.Black;
        }

        labelOutput.Text += "<br><br>" + "The number is: " +
           myCompareValidate.ValueToCompare;
     }

  </script>
</HEAD>
    <body>
      <form runat="server" ID="myForm">
        <h3>IValidator Example demonstrating IsValid & ErrorMessage</h3>
        <h5>Guess!! a number between 1 and 10 :</h5>
        <asp:TextBox id="myTextBox" runat="server" />
        <asp:CompareValidator id="myCompareValidate"
             ControlToValidate="myTextBox" ValueToCompare="0"
             EnableClientScript="False" Type="Integer" Text="*"
             runat="server" />
        <br>
        <asp:Button Text="Submit" OnClick="Button_Click" runat="server" />
        <br>
        <asp:Label id="labelOutput" runat="server" />
        <br>
        <asp:ValidationSummary id="Summary1" runat="server" />
     </form>
  </body>
</HTML>
J# 
<HTML>
  <HEAD>
    <script language="VJ#" runat="server">

    void Button_Click(Object sender, EventArgs e)
    {
        // Generating the random number.
        Random randNumber = new Random();
        myCompareValidate.set_ValueToCompare(
            System.Convert.ToString(randNumber.Next(1, 10)));

        // Setting the ErrorMessage.
        myCompareValidate.set_ErrorMessage("Try Again!!");
        myCompareValidate.Validate();

        // Check for Validity of control.
        if (myCompareValidate.get_IsValid() 
            && (!(myTextBox.get_Text().Equals("")))) {
            labelOutput.set_Text("You guessed correctly!!");
            labelOutput.set_ForeColor(System.Drawing.Color.get_Blue());
        }
        else {
            labelOutput.set_Text("You guessed poorly");
            labelOutput.set_ForeColor(System.Drawing.Color.get_Black());
        }
        labelOutput.set_Text(labelOutput.get_Text() + "<br><br>" 
            + "The number is: " + myCompareValidate.get_ValueToCompare());
    } //Button_Click

  </script>
</HEAD>
    <body>
      <form runat="server" ID="myForm">
        <h3>IValidator Example demonstrating IsValid & ErrorMessage</h3>
        <h5>Guess!! a number between 1 and 10 :</h5>
        <asp:TextBox id="myTextBox" runat="server" />
        <asp:CompareValidator id="myCompareValidate"
             ControlToValidate="myTextBox" ValueToCompare="0"
             EnableClientScript="False" Type="Integer" Text="*"
             runat="server" />
        <br>
        <asp:Button ID="Button1" Text="Submit" OnClick="Button_Click" runat="server" />
        <br>
        <asp:Label id="labelOutput" runat="server" />
        <br>
        <asp:ValidationSummary id="Summary1" runat="server" />
     </form>
  </body>
</HTML>
平台

Windows 98、Windows 2000 SP4、Windows Server 2003、Windows XP Media Center Edition、Windows XP Professional x64 Edition、Windows XP SP2、Windows XP Starter Edition

.NET Framework 并不是对每个平台的所有版本都提供支持。有关受支持版本的列表，请参见系统要求。
版本信息

.NET Framework

受以下版本支持：2.0、1.1、1.0
请参见
标记 :


Page view tracker