The below code snippet will help us to display a string as an image in ASP.Net page. In the below code snippet, we first create Bitmap object with dimension of the image and use Graphics class in System.Drawing namespace to write the string in the created bitmap object. The created bitmap object is then converted to byte array and displayed in the page.

Refer the below code for complete understanding.

<%@ WebHandler Language="C#" Class="GenerateImage" %>

using System;

using System.Web;

using System.Drawing;

using System.IO;

public class GenerateImage : IHttpHandler {

    public void ProcessRequest (HttpContext context) {

        string strDisplay = "CodDigest.Com";

        Bitmap bmpOut = new Bitmap(200, 50);

        Graphics g = Graphics.FromImage(bmpOut);

        g.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.HighQualityBicubic;

        g.FillRectangle(Brushes.Black,0,0,200,50);

        g.DrawString(strDisplay, new Font("Verdana", 18), new SolidBrush(Color.White), 0, 0);      

        MemoryStream ms = new MemoryStream();       

        bmpOut.Save(ms, System.Drawing.Imaging.ImageFormat.Png);

        byte[] bmpBytes = ms.GetBuffer();

        bmpOut.Dispose();

        ms.Close();

        context.Response.BinaryWrite(bmpBytes);

        context.Response.End();

    }

    public bool IsReusable {

        get {

            return false;

        }

    }

}