SharePoint InputFormTextBox Rich Text Validation

I had some problems validating SharePoint InputFormTextBox with InputFormRequiredFieldValidator.  The problem is that it always shows the InputFormTextBox as invalid even tho I did have some content in the text box.  And if you click the submit button the second time, the validation just doesn't work any more.

To get around it, I had to use the ASP.NET custom validator.  I found this way from other blogs online so it's nothing new.  However, there is a key attribut that a lot of blog forgot to mention.  Below is my code snippet.

function ValidateMessageBody(source, args) {

    try {

        //Create Rich TextBox Editor control object 

        var docEditor = RTE_GetEditorDocument(source.controltovalidate);

        if (null == docEditor)

            return;

        var strHtml = docEditor.body.innerText;

        if (strHtml == "") {

            args.IsValid = false;

            return;

        }

    } catch (err) { }

    args.IsValid = true;

}

<SharePoint:InputFormTextBox  runat="server" ID="iftxtText" Rows="10" RichText="true" RichTextMode="Compatible" AllowHyperlink="true" TextMode="MultiLine" />

<asp:CustomValidator cssClass="redText" ID="cvOverview" ClientValidationFunction="ValidateMessageBody" ValidateEmptyText="true" runat="server" ValidationGroup="SaveClick" ControlToValidate="iftxtText" Display="Dynamic" ErrorMessage="Required"></asp:CustomValidator>

The ValidateEmptyText attribute is required to set to true for this to work.  It's so easy and yet took me a lot of time because I wasn't aware of this.   Hopefully, it'll help others.