<%@ Register Assembly="AsyncControls" Namespace="DelvingWare.AsyncControls" TagPrefix="dw" %>

<dw:AsyncPanel runat="server" ID="pnlOne" CssClass="liveDemoSectionDiv">

    <div class="liveDemoSectionTitle">Multi-Validation (Date/Required Field)</div>
    <dw:AsyncTextBox ID='txtMain' runat="server" CssClass="forms" />
    
    <dw:AsyncButton runat="server" ID="btOne"
    CausesStrictValidation="true"
    CssClass="greyButton">Validate</dw:AsyncButton>

    <br />
    
    <dw:AsyncValidator ID="txtV" runat="server" 
        ControlToValidate="txtMain"
        ErrorMessage="Please enter a date. " 
        ErrorMessageCssClass="errorMsg" />
        
    <dw:AsyncValidator id="txtV2" runat="server"
        ControlToValidate="txtMain"
        ErrorMessage="Please enter a valid date." 
        ErrorMessageCssClass="errorMsg" 
        Operator="dataTypeCheck"
        Type=Date Validation="Compare" />
        
</dw:AsyncPanel>

<dw:AsyncPanel runat="server" ID="pnlTwo" CssClass="liveDemoSectionDiv">
    <div class="liveDemoSectionTitle">Compare Validator (w/ Internal Required Field)</div>
    <dw:AsyncTextBox runat="server" ID="txtCmp"
    ErrorMessageCssClass="errorMsg"
    ErrorMessage="Required Field"
    EnableValidation="Enabled" />
    
    <dw:AsyncButton runat="server" ID="btTwo"
    CausesStrictValidation="true"
    CssClass="greyButton">Validate</dw:AsyncButton>
    
    <br />
    
    <dw:AsyncValidator runat="server" ID="cmpV"
    ControlToValidate="txtCmp"
    ErrorMessage="Numbers only."
    ErrorMessageCssClass="errorMsg"
    Operator="DataTypeCheck"
    Type="Integer" 
    Validation="Compare" />
    
</dw:AsyncPanel>

<dw:AsyncPanel runat="server" ID="pnlThree" CssClass="liveDemoSectionDiv">
<div class="liveDemoSectionTitle">Required Field Validator</div>
    
    <dw:AsyncTextBox runat="server" ID="txtReqField" />
    
    <dw:AsyncButton runat="server" ID="btThree"
    CausesStrictValidation="true"
    CssClass="greyButton">Validate</dw:AsyncButton>
    <br />
    
    <!-- It performs Required Field validation by default -->
    <dw:AsyncValidator runat="server" ID="reqFieldV"
    ControlToValidate="txtReqField"
    ErrorMessageCssClass="errorMsg">Required field.</dw:AsyncValidator>
    
</dw:AsyncPanel>

<dw:AsyncPanel runat="server" ID="pnlFour" CssClass="liveDemoSectionDiv">
<div class="liveDemoSectionTitle">Range Validator</div>
    
    <dw:AsyncTextBox runat="server" ID="txtRange" />
    
    <dw:AsyncButton runat="server" ID="btFour"
    CausesStrictValidation="true"
    CssClass="greyButton">Validate</dw:AsyncButton>
    <br />
    
    <dw:AsyncValidator runat="server" ID="rangeV"
    ControlToValidate="txtRange"
    ErrorMessageCssClass="errorMsg"
    MinimumValue="100"
    MaximumValue="150"
    Validation="Range">Value must be between <b>100</b> and <b>150.</b></dw:AsyncValidator>
    
</dw:AsyncPanel>

<dw:AsyncPanel runat="server" ID="pnlFive" CssClass="liveDemoSectionDiv">
<div class="liveDemoSectionTitle">Regular Expression Validator (w/Internal Required Field)</div>

    <p style="font-family: Trebuchet MS, Arial; font-size: 10pt;">
    This AsyncValidator supports RegexOptions, such as IgnoreCase, Multiline, etc. 
    </p>
    
    Type <b>AsyncControls</b> (case-insensitive): 
    <br />
    <dw:AsyncTextBox runat="server" ID="txtRegex"
    EnableValidation="Enabled"
    ErrorMessage="Required Field"
    ErrorMessageCssClass="errorMsg" />
    
    <dw:AsyncButton runat="server" ID="btFive"
    CausesStrictValidation="true"
    CssClass="greyButton">Validate</dw:AsyncButton>
    <br />
    
    <dw:AsyncValidator runat="server" ID="regexV"
    ControlToValidate="txtRegex"
    ErrorMessageCssClass="errorMsg"
    ValidationExpression="asynccontrols"
    ValidationExpressionOptions="IgnoreCase"
    Validation="RegularExpression">Please type: AsyncControls.</dw:AsyncValidator>

</dw:AsyncPanel>

<dw:AsyncPanel runat="server" ID="pnlSix" CssClass="liveDemoSectionDiv">
<div class="liveDemoSectionTitle">AsyncListControl Validator</div>
    
    <dw:AsyncDropDownList runat="server" ID="drpList">
        <dw:AsyncListItem Value="none" />
        <dw:AsyncListItem Value="one">One</dw:AsyncListItem>
        <dw:AsyncListItem Value="two">Two</dw:AsyncListItem>
    </dw:AsyncDropDownList>
    
    <dw:AsyncButton runat="server" ID="btSix"
    CausesStrictValidation="true"
    CssClass="greyButton">Validate</dw:AsyncButton>
    <br />
    
    <dw:AsyncValidator runat="server" ID="drpV"
    ControlToValidate="drpList"
    ErrorMessage="Please select a valid list item."
    ErrorMessageCssClass="errorMsg"
    InitialValue="none" />

</dw:AsyncPanel>

<dw:AsyncLabel runat="server" ID="lblMain" 
RenderMode="paragraph">Test validation.</dw:AsyncLabel>

<dw:AsyncButton runat="server" ID="btMain" 
CausesValidation="true" 
OnClick="btMain_Click"
CssClass="greyButton">Validate All</dw:AsyncButton>

using System;
using DelvingWare.AsyncControls;
...
protected void btMain_Click( object sender, AsyncEventArgs ae )
{
    // ensure the page validation was successful
    if ( AsyncPage.IsValid )
    {
        // update the AsyncLabel text
        lblMain.Text = "All fields are valid.";
    } 
    else
    {
        // create working string instance to work with
        string lblString = "<u>Validation Summary</u><br />";

        // append all the pages validation collection summaries for each failed validator
        foreach( AsyncValidatorItem vi in AsyncPage.ValidatorCollection )
        {
            lblString += "<p class='errorSummary'>"+ vi.ErrorMessage +"</p>";
        } // end FOREACH

        // append trailing suggestion
        lblString += "<br /><u>Please check fields.</u>";

        // show the message box to the user for 4.2 seconds
        AsyncPage.MessageBox(lblString, 4200);

        // update the AsyncLabel text
        lblMain.Text = AsyncPage.ValidatorCollection.Count +" field(s) failed validation.";
    }
}

Imports System
Imports DelvingWare.AsyncControls
...

Protected Sub btMain_Click(ByVal sender As Object, ByVal ae As AsyncEventArgs)
    ' ensure the page validation was successful
    If AsyncPage.IsValid Then
        ' update the AsyncLabel text
        lblMain.Text = "All fields are valid."
    Else
        ' create working string instance to work with
        Dim lblString As String = "<u>Validation Summary</u><br />"
        ' append all the pages validation collection summaries for each failed validator
        For Each vi As AsyncValidatorItem In AsyncPage.ValidatorCollection
            lblString = (lblString + ("<p class='errorSummary'>"  _
                        + (vi.ErrorMessage + "</p>")))
        Next
        ' end FOREACH
        ' append trailing suggestion
        lblString = (lblString + "<br /><u>Please check fields.</u>")
        ' show the message box to the user for 4.2 seconds
        AsyncPage.MessageBox(lblString, 4200)
        ' update the AsyncLabel text
        lblMain.Text = (AsyncPage.ValidatorCollection.Count + " field(s) failed validation.")
    End If
End Sub

.asyncValidatorDemo 

{
    width: 518px;
    font-family: Verdana, Arial, Serif;
}