How to Generate Popup window on method called or button click

In this I am explaining how to display Message Boxes in ASP.Net using JavaScript. ASP.Net. With the use of JavaScript alert we can display messages on different events in an ASP.Net Web Application.

C# code is given Below....

protected void Page_Load(object sender, EventArgs e)

{

  string message = "Hello! Mudassar.";

  System.Text.StringBuilder sb = new System.Text.StringBuilder();

  sb.Append("<script type = 'text/javascript'>");

  sb.Append("window.onload=function(){");

  sb.Append("alert('");

  sb.Append(message);

  sb.Append("')};");

  sb.Append("</script>");

  ClientScript.RegisterClientScriptBlock(this.GetType(), "alert", sb.ToString());

}

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