In this article I will explain with an example, how to add images to 
TinyMCE Rich TextBox Editor using ASP.Net FileUpload control in ASP.Net using C# and VB.Net.
		 
	
		 
	
		HTML Markup
	
		The following HTML Markup consists of:
	
		TextBox  – For capturing text.
	
		The TextBox has been assigned with TextMode property set to MultiLine.
	
		FileUpload – For selecting image file.
	
	
		The Buttons have been assigned with OnClick event handler.
	
		Label – For displaying content of TinyMCE Rich Text Box.
	
		Thee Label has been assigned with Visible property set to false.
	
		
			<asp:FileUpload ID="fuUpload" runat="server" />
		
			<asp:Button ID="btnUpload" runat="server" Text="Upload" OnClick="Upload" /><br />
		
			<br />
		
			<asp:TextBox ID="RichTextBox" runat="server" TextMode="MultiLine"></asp:TextBox>
		
			<br />
		
			<asp:Button ID="btnSave" runat="server" Text="Save" OnClick="Save" />
		
			<hr />
		
			<asp:Label ID="lblDisplay" runat="server" Text="" Visible="false"></asp:Label>
	 
	
		 
	
		 
	
		Applying the TinyMCE Plugin to the TextBox
	
		TinyMCE plugin implementation
	
		Inside the HTML, the following 
TinyMCE JS file is inherited.
		1. tinymce.min.js
	
		Inside the 
Init event handler of the 
TinyMCE plugin, the plugin is applied to the TextArea element i.e. 
Multiline TextBox
		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="https://cdnjs.cloudflare.com/ajax/libs/tinymce/4.0.20/tinymce.min.js"></script>
		
			<script> type="text/javascript">
		
			    tinymce.init({ selector: 'textarea', width: 300 });
		
			</script>
	 
	
		 
	
		 
	
		Uploading Image to TinyMCE Rich Text Editor
	
		When Upload button is clicked, the FileUpload control is checked for file if it has file then, it is saved in the Images folder.
	
	
		C#
	
		
			 protected void Upload(object sender, EventArgs e)
		
			{
		
			    if (fuUpload.HasFile)
		
			    {
		
			        string fileName = Path.GetFileName(fuUpload.PostedFile.FileName);
		
			        string filePath = "Images/" + fileName;
		
			        fuUpload.SaveAs(Server.MapPath(filePath));
		
			        RichTextBox.Text += string.Format("<img src='{0}' alt='{1}' style='height:150px;width:150px' />", filePath, fileName);
		
			    }
		
			}
	 
	
		 
	
		VB.Net
	
		
			Protected Sub Upload(ByVal sender As Object, ByVal e As EventArgs)
		
			    If fuUpload.HasFile Then
		
			        Dim fileName As String = Path.GetFileName(fuUpload.PostedFile.FileName)
		
			        Dim filePath As String = "Images/" & fileName
		
			        fuUpload.SaveAs(Server.MapPath(filePath))
		
			        RichTextBox.Text += String.Format("<img src='{0}' alt='{1}' style='height:150px;width:150px' />", filePath, fileName)
		
			    End If
		
			End Sub
	 
	
		 
	
		 
	
		Saving TinyMCE Rich Text Editor content 
	
		When 
Save button is clicked, the 
Visible property of the Label control is set to true and contents of the 
TinyMCE Rich TextBox Editor is set to it.
		C#
	
		
			protected void Save(object sender, EventArgs e)
		
			{
		
			    lblDisplay.Visible = true;
		
			    lblDisplay.Text = RichTextBox.Text;
		
			}
	 
	
		 
	
		VB.Net
	
		
			Protected Sub Save(ByVal sender As Object, ByVal e As EventArgs)
		
			    lblDisplay.Visible = True
		
			    lblDisplay.Text = RichTextBox.Text
		
			End Sub
	 
	
		 
	
		 
	
		Screenshot
	![Adding Images to TinyMCE Rich Text Editor using ASP.Net FileUpload Control]() 
	
		 
	
		 
	
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