创建服务器控件。创建问题

Question

I create a new server control. See the code below:

 public class Tree : Control
    {
        #region Rendering
        protected override void Render(HtmlTextWriter output)
        {
            RenderInputTag(output);
        }

        private void RenderInputTag(HtmlTextWriter htw)
        {
            //Javascript
            htw.AddAttribute(HtmlTextWriterAttribute.Type, "text/javascript");
            htw.RenderBeginTag(HtmlTextWriterTag.Script);
            htw.Write("<%@ Register Src=\"~/Controls/TreeJavascript.ascx\" TagName=\"Tree\" TagPrefix=\"flt\"%>");
            htw.RenderEndTag();
        }

        #endregion
    }

But I get the following error, when I want to use the controller:

Uncaught SyntaxError: Unexpected token <

how to fix it?

This is the rendered HTML:

<script type=text/javascript>
    <%@ Register Src=\"~/Controls/TreeJavascript.ascx\" TagName=\"Tree\" TagPrefix=\"flt\"%>
</script>

Answer 1

Since you say the output is this:

<script type=text/javascript>
    <%@ Register Src=\"~/Controls/TreeJavascript.ascx\" TagName=\"Tree\" TagPrefix=\"flt\"%>
</script>

It is pretty clear the cause of the issue is that the server side tag isn't rendered into code in the HTML. Since <% isn't valid in javascript, it breaks.

I think you should initialize the control in code, and call RenderControl on it:

TreeJavascript t = new TreeJavascript();
t.RenderControl(htw);

Else, if the content is just static, save the javascript in a variable and put it in here.