Back to Devexpress

ASPxClientCaptcha.Refresh Method

aspnet-js-aspxclientcaptcha-4c2d909d.md

latest3.1 KB
Original Source

ASPxClientCaptcha.Refresh Method

Refreshes the code displayed within the editor’s challenge image.

Declaration

ts
Refresh(): void

Remarks

To update image, the Refresh method sends a callback to the server, and rerenders an editor.

The Refresh method is useful to implement custom functionality when the refresh button is invisible.

Example

The following part of the ASPxCaptcha - Custom Appearance online demo illustrates how to implement a captcha control with a custom appearance.

In this example, the control’s Refresh Button.ASPxCaptcha and Text Box.ASPxCaptcha are hidden, and their functionaliry is implemented in a custom manner using separate controls (the IMG element, ASPxLabel, ASPxTextBox).

javascript
function GetRefreshButton() {
    return document.getElementById("refreshButton");
}        

function OnCaptchaBeginCallback(s, e) {
    var refreshButton = GetRefreshButton();
    refreshButton.src = "Images/refreshButtonAnimated.gif";
}

function OnCaptchaEndCallback(s, e) {
    var refreshButton = GetRefreshButton();
    refreshButton.src = "Images/refreshButton.gif"; 
    tbCode.SetValue("");
...   
}
aspx

...
<dx:ASPxCaptcha ID="Captcha" runat="server" SkinID="dummy" ClientInstanceName="captcha" 
CodeLength="6">
    <ChallengeImage BackgroundColor="Transparent" ForegroundColor="#676767" BorderWidth="0"
        Height="72" />
    <ValidationSettings EnableValidation="False">
    </ValidationSettings>
    <TextBox Visible="False" />
    <RefreshButton Visible="False">
    </RefreshButton>
    <LoadingPanel Enabled="False" />
    <ClientSideEvents BeginCallback="OnCaptchaBeginCallback" 
        EndCallback="OnCaptchaEndCallback" />
</dx:ASPxCaptcha>
...
<dx:ASPxLabel ID="lblCode" runat="server" AssociatedControlID="tbCode" Text="Type the code">
</dx:ASPxLabel>
...
<dx:ASPxTextBox ID="tbCode" runat="server" Width="200px" AutoCompleteType="Disabled"
    BackColor="Transparent" ClientInstanceName="tbCode">
    <Border BorderWidth="0px" />
</dx:ASPxTextBox>
...
<dx:ASPxButton ID="btnSubmit" runat="server" Text="Submit" UseSubmitBehavior="true"
    AutoPostBack="true" Width="175px">
</dx:ASPxButton>

See Also

Captcha Control

ASPxClientCaptcha Class

ASPxClientCaptcha Members