//圖片轉為base64編碼的字串
		protected string ImgToBase64String(string Imagefilename)
		{
			try
			{
				Bitmap bmp = new Bitmap(Imagefilename);
 
				MemoryStream ms = new MemoryStream();
				bmp.Save(ms, System.Drawing.Imaging.ImageFormat.Jpeg);
				byte[] arr = new byte[ms.Length];
				ms.Position = 0;
				ms.Read(arr, 0, (int)ms.Length);
				ms.Close();
				return Convert.ToBase64String(arr);
			}
			catch (Exception ex)
			{
				return null;
			}
		}
 
		//threeebase64編碼的字串轉為圖片
		protected Bitmap Base64StringToImage(string strbase64)
		{
			try
			{
				byte[] arr = Convert.FromBase64String(strbase64);
				MemoryStream ms = new MemoryStream(arr);
				Bitmap bmp = new Bitmap(ms);
 
				 bmp.Save(@"d:\test.jpg", System.Drawing.Imaging.ImageFormat.Jpeg);
				//bmp.Save(@"d:\"test.bmp", ImageFormat.Bmp);
				//bmp.Save(@"d:\"test.gif", ImageFormat.Gif);
				//bmp.Save(@"d:\"test.png", ImageFormat.Png);
				ms.Close();
				return bmp;
			}
			catch (Exception ex)
			{
				return null;
			}
		}
 

2: 圖片直接顯示

    string Base64String = "";//太長就不貼出來了
 
            byte[] bytes = Convert.FromBase64String(Base64String);
            ImageTagId.ImageUrl = "data:image/jpeg;base64," + Convert.ToBase64String(bytes);//

3：

public System.Drawing.Image Base64ToImage(string base64String)
        {
            byte[] imageBytes = Convert.FromBase64String(base64String);
            MemoryStream ms = new MemoryStream(imageBytes, 0, imageBytes.Length);
            ms.Write(imageBytes, 0, imageBytes.Length);
            System.Drawing.Image image = System.Drawing.Image.FromStream(ms, true);
            return image;
        }
 
使用方法：
 
    Base64ToImage(dd).Save(Server.MapPath("Hello.jpg"));
   Image1.ImageUrl = "Hello.jpg";
 

4：轉換成圖片另存為然後圖片顯示出來

string dd = "";//太長就不貼出來了
 
            var bytes = Convert.FromBase64String(dd);
            using (var imageFile = new FileStream(@"d:\Hello1.jpg", FileMode.Create))
            {
                imageFile.Write(bytes, 0, bytes.Length);
                imageFile.Flush();
            }
 

5://直接轉換存為路徑下圖片

    string base64Str=""/
 
 byte[] bytes = System.Convert.FromBase64String(dd);
 
           File.WriteAllBytes(@"d:\newfile.jpg", bytes);
     string filePath = @"d:\MyImage.jpg";
      File.WriteAllBytes(filePath, Convert.FromBase64String(base64Str));
 
 

6：多張base64圖片轉換為圖片另存為

public string Base64ToImage(string upimgPath, string base64String)
    {
      string goodspath = Server.MapPath(upimgPath);  //用來生成資料夾
      if (!Directory.Exists(goodspath))
      {
        Directory.CreateDirectory(goodspath);
      }
      var imgPath = string.Empty;
      if (!string.IsNullOrEmpty(base64String))
      {
        var splitBase = base64String.Split(new char[] { ';' }, StringSplitOptions.RemoveEmptyEntries);
        foreach (var item in splitBase)
        {
          var path = upimgPath + Guid.NewGuid() + ".jpg";
 
          string filePath = Server.MapPath(path);// Server.MapPath(upimgPath + Guid.NewGuid() + ".jpg");
          File.WriteAllBytes(filePath, Convert.FromBase64String(item));
          imgPath += path + ";";
        }
      }
      else { imgPath = ";"; }
      return imgPath.TrimEnd(';');
    }

使用方法:

va headimg="";

 Base64ToImage("UpLoadImg/HeadImage/", headimg)

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