//图片转为base64编码的字符串

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编码的字符串转为图片

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;

}

}

//图片转为base64编码的字符串

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编码的字符串转为图片

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: 图片直接显示

string Base64String = "";//太长就不贴出来了

byte[] bytes = Convert.FromBase64String(Base64String);

ImageTagId.ImageUrl = "data:image/jpeg;base64," + Convert.ToBase64String(bytes);//

//

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：转换成图片另存为然后图片显示出来

string dd = "";//太长就不贴出来了

var bytes = Convert.FromBase64String(dd);

using (var imageFile = new FileStream(@"d:\Hello1.jpg", FileMode.Create))

{

imageFile.Write(bytes, 0, bytes.Length);

imageFile.Flush();

}

//5://直接转换存为路径下图片

string base64Str=""/

e[] bytes = System.Convert.FromBase64String(dd);

File.WriteAllBytes(@"d:\newfile.jpg", bytes);

string filePath = @"d:\MyImage.jpg";

File.WriteAllBytes(filePath, Convert.FromBase64String(base64Str));

6：多张base64图片转换为图片另存为

public string Base64ToImage(string upimgPath, string base64String)

{

string goodspath = Server.MapPath(upimgPath); //用来生成文件夹

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)