Dear @Coders3,
You would need to create a custom textbox which can show complex HTML content to do that. Or, you could use WebBrowser control instead. instead of using multiline textbox you can use "Literal" or "iframe". please refer below articles.
https://forums.asp.net/t/1034064.aspx?how+to+display+html+content+on+textbox
https://forums.asp.net/t/1954982.aspx?how+to+display+text+without+html+text+on+textbox
please refer below sample code by using below reference
http://www.aspforums.net/Threads/771987/Read-and-display-HTML-file-in-Textboxmultiline-ASPNET/
Test.html
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<title></title>
</head>
<body>
<table>
<tr>
<td>
Id
</td>
<td>
Name
</td>
</tr>
<tr>
<td>
1
</td>
<td>
John Hammond
</td>
</tr>
<tr>
<td>
2
</td>
<td>
Mudassar Khan
</td>
</tr>
</table>
</body>
</html>
Default.aspx
<%@ Page Language="C#" AutoEventWireup="true" CodeFile="Default.aspx.cs" Inherits="_Default" %>
<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
<title></title>
</head>
<body>
<form id="form1" runat="server">
<div>
<table>
<tr>
<td>
<asp:Literal ID="Ltrl1" runat="server"></asp:Literal>
<iframe src="Test.html" height="200" width="300" style="border:none;"></iframe>
</td>
</tr>
</table>
</div>
</form>
</body>
</html>
Default.aspx.cs
public partial class _Default : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
Ltrl1.Text = Server.HtmlDecode(System.IO.File.ReadAllText(Server.MapPath("~/Test.html")));
}
}
in my code i am used both "literal" and "iframe" controls. please use any one asper your requirement.