//base64编码的文本 转为    图片  

        private void button2_Click(object sender, EventArgs e)  

        {  

            OpenFileDialog dlg = new OpenFileDialog();  

            dlg.Title = "选择要转换的base64编码的文本";  

            dlg.Filter = "txt files
------解决方案--------------------
*.txt";  

            if (DialogResult.OK == dlg.ShowDialog())  

            {  

                Base64StringToImage(dlg.FileName);  

            }  

        }  

        //base64编码的文本 转为    图片  

        private void Base64StringToImage(string txtFileName)  

        {  

            try  

            {  

                FileStream ifs = new FileStream(txtFileName, FileMode.Open, FileAccess.Read);  

                StreamReader sr = new StreamReader(ifs);  

  

                String inputStr = sr.ReadToEnd();  

                byte[] arr = Convert.FromBase64String(inputStr);  

                MemoryStream ms = new MemoryStream(arr);  

                Bitmap bmp = new Bitmap(ms);  

  

                bmp.Save(txtFileName + ".jpg", System.Drawing.Imaging.ImageFormat.Jpeg);  

                //bmp.Save(txtFileName + ".bmp", ImageFormat.Bmp);  

                //bmp.Save(txtFileName + ".gif", ImageFormat.Gif);  

                //bmp.Save(txtFileName + ".png", ImageFormat.Png);  

             &