windows phone开发之图片上传

首先是 后台类

/// <summary> /// 上传文件

/// </summary>

public class UploadFile

{

public UploadFile()

{ }

/// <summary>

/// 根据文件名、文件类型与文件流实现化

/// </summary>

/// <param name="fileName">文件名</param>

/// <param name="stream">文件数据流</param>

public UploadFile(string fileName, Stream stream)

{

this.FileName = System.IO.Path.GetFileName(fileName);

this.ContentType = GetContentType(this.FileName);

this.FileStream = stream;

}

/// 文件名称

public string FileName { get; private set; }

/// 文件类型

public string ContentType { get; private set; }

/// 本地文件路径

private string FilePath { get; set; }

/// 文件数据流

public Stream FileStream { get; private set; }

/// 将当前的文件数据写入到某个数据流中

/// <param name="stream"></param>

public void WriteTo(Stream stream)

byte[] buffer = new byte[512];

int size = 0;

if (this.FileStream != null)

{

//写入文件流

while ((size = this.FileStream.Read(buffer, 0, buffer.Length)) > 0)

{

stream.Write(buffer, 0, size);

}

}

if (!string.IsNullOrEmpty(this.FilePath)

&& File.Exists(this.FilePath))

//写入本地文件流

using (System.IO.FileStream reader = new FileStream(this.FilePath, FileMode.Open, FileAccess.Read))

while ((size = reader.Read(buffer, 0, buffer.Length)) > 0)

{

stream.Write(buffer, 0, size);

}

/// 根据文件扩展名获取文件类型

/// <returns></returns>

private static string GetContentType(string fileName)

var fileExt = System.IO.Path.GetExtension(fileName);

return GetCommonFileContentType(fileExt);

/// 获取通用文件的文件类型

/// <param name="fileExt">文件扩展名.如".jpg",".gif"等</param>

private static string GetCommonFileContentType(string fileExt)

switch (fileExt)

case ".jpg":

case ".jpeg":

return "image/jpeg";

case ".gif":

return "image/gif";

case ".bmp":

return "image/bmp";

case ".png":

return "image/png";

default:

return "application/octetstream";

/// 压缩图片，只调整质量，不调整分辨率

/// <param name="soucre">图片流</param>

/// <param name="quality">质量1-100</param>

public static Stream Compression(Stream soucre)

var quality = 80;

soucre.Seek(0, SeekOrigin.Begin);

var p = quality / 100.0;

var writeableBitmap = PictureDecoder.DecodeJpeg(soucre);

var width = writeableBitmap.PixelWidth * p;

var height = writeableBitmap.PixelHeight * p;

var outstream = new MemoryStream();

writeableBitmap.SaveJpeg(outstream, (int)width, (int)height, 0, quality);

outstream.Seek(0, SeekOrigin.Begin);

return outstream;

}

}

然后是前台的调用

/// <summary> /// 图片上传处理

/// <param name="sender"></param>

/// <param name="e"></param>

private void PhotoChooserTask_Completed(object sender, PhotoResult e)

try

if (e.ChosenPhoto != null)

Stream s = UploadFile.Compression(e.ChosenPhoto);

bytepic = StreamToBytes(s);

Encoding myEncoding = Encoding.GetEncoding("utf-8");

strpic = Convert.ToBase64String(bytepic);

ExistsPic = true;

catch (Exception)

throw;

/// <summary>

/// 字节流转换byte

/// <param name="stream"></param>

/// <returns></returns>

public byte[] StreamToBytes(Stream stream)

byte[] bytes = new byte[stream.Length];

stream.Read(bytes, 0, bytes.Length);

// 设置当前流的位置为流的开始

stream.Seek(0, SeekOrigin.Begin);

return bytes;