https://learn.microsoft.com/fr-fr/dotnet/api/system.web.ui.webcontrols.webcontrol.renderendtag?view=netframework-4.8.1
WebControl.RenderEndTag(HtmlTextWriter) Method (System.Web.UI.WebControls) | Microsoft Learn
Renders the HTML closing tag of the control into the specified writer. This method is used primarily by control developers.
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