--泛型處理常式的內容
using ThoughtWorks.QRCode.Codec;
using ThoughtWorks.QRCode.Codec.Data;
using ThoughtWorks.QRCode.Codec.Util;
using System.IO;
using System.Text;

public class GetQRCode : IHttpHandler {

public void ProcessRequest (HttpContext context) {

    String data = context.Request["CodeText"];
    if (!string.IsNullOrEmpty(data))
    {
        QRCodeEncoder qrCodeEncoder = new QRCodeEncoder();
        qrCodeEncoder.QRCodeEncodeMode = QRCodeEncoder.ENCODE_MODE.BYTE;
        qrCodeEncoder.QRCodeScale = 4;
        qrCodeEncoder.QRCodeVersion = 8;
        qrCodeEncoder.QRCodeErrorCorrect = QRCodeEncoder.ERROR_CORRECTION.M;
        System.Drawing.Bitmap image = qrCodeEncoder.Encode(data);
        System.IO.MemoryStream MStream = new System.IO.MemoryStream();
        image.Save(MStream, System.Drawing.Imaging.ImageFormat.Png);
        context.Response.ClearContent();
        context.Response.ContentType = "image/Png";
        context.Response.BinaryWrite(MStream.ToArray());
    }

    context.Response.Flush();
    context.Response.End();
}

--顯示qrcode的頁面程式
Image1.ImageUrl = "../UserControl/GetQRCode.ashx?CodeText=" + CodeText;
原先這樣可以使用，可是要搬到共用的程式裡面，泛型處理常式的程式如何改成app_code的共用程式中，因為image使用方式有限制。