Hello Marc,

In addition to the code snippet you have shared, you will also need to attach the OnAjaxUpdate event to the Grid and update the ContentTemplateContainer with the ToolTip value.

Sample C# code

protected void OnAjaxUpdate(object sender, ToolTipUpdateEventArgs args)
{ 
    string ttValue = args.Value;
    //use the value to populate the toolip (fetch data from a database or to set properties of a user control)
    //the below line directly sets its as text for the tooltip:
    args.UpdatePanel.ContentTemplateContainer.Controls.Add(new LiteralControl(ttValue));
}

I have updated the documentation article to explicitly mention that. Here is the Git commit: docs(tooltip): fix snippets. Changes will be applied within an hour counting from the time the Commit was pushed to the production branch.

Kind regards,

Doncho
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