In this article I will explain with an example, how to add TinyMCE Rich TextBox Editor in ASP.Net.
HTML Markup
The following HTML Markup consists of:
TextBox – For capturing Text.
TextBox has been assigned with a TextMode property set to MultiLine.
Button – For setting TextBox content to the Label.
The Button has been assigned with an OnClick event handler.
Label – For displaying TextBox content.
<asp:TextBox ID="txtTinyMCE" runat="server" TextMode="MultiLine"></asp:TextBox>
<br />
<asp:Button ID="btnSubmit" runat="server" Text="Submit" OnClick="Submit" />
<hr />
<asp:Label ID="lblContent" runat="server"></asp:Label>
TinyMCE plugin implementation
Inside the HTML, the following TinyMCE JS file is inherited.
1. tinymce.min.js
The TinyMCE plugin has been applied to TextArea element.
Note: The ASP.Net Multiline TextBox is rendered as TextArea element in HTML, hence the TinyMCE plugin has been applied to TextArea element.
<script type="text/javascript" src=""></script>
<script type="text/javascript">
    tinymce.init({ selector: 'textarea', width: 300 });
Displaying the TinyMCE Rich Text Content
When Submit Button is clicked, the contents of the TinyMCE Rich TextBox Editor are set to the Label control.
protected void Submit(object sender, EventArgs e)
    lblContent.Text = txtTinyMCE.Text;
Protected Sub Submit(sender As Object, e As System.EventArgs)
    lblContent.Text = txtTinyMCE.Text
End Sub
Possible Error
The following error occurs when you try to submit HTML content to server.
Using Tiny MCE Rich TextBox in ASP.Net
The solution to this problem is provided in the following article.
Using Tiny MCE Rich TextBox in ASP.Net
Browser Compatibility
The above code has been tested in the following browsers.
Internet Explorer  FireFox  Chrome  Safari  Opera
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