/// <summary>
/// 检测上传的媒体是否满足基本要求
/// </summary>
/// <param name="media"></param>
/// <returns></returns>
private BasicResult MediaChecker(LocalMedia media)
{
var sizes = new Dictionary <string, long>
{
{ Media.Image, 128 * 1024 },
{ Media.Voice, 256 * 1024 },
{ Media.Video, 1 * 1024 * 1024 },
{ Media.Thumb, 64 * 1024 },
};
if (media == null)
{
return(BasicResult.GetFailed("缺少媒体参数"));
}
if (!File.Exists(media.MediaPath))
{
return(BasicResult.GetFailed("指定的媒体文件不存在"));
}
if (string.IsNullOrEmpty(media.MediaType))
{
return(BasicResult.GetFailed("未指定媒体类型"));
}
if (new FileInfo(media.MediaPath).Length > sizes[media.MediaType])
{
return(BasicResult.GetFailed(string.Format("指定的媒体文件超过限制大小{0}K", sizes[media.MediaPath] / 1024)));
}
return(BasicResult.GetSuccess());
}
/// <summary>
/// 下载媒体文件。
/// 如果下载成功，返回值的ErrMsg属性携带保存的文件全路径
/// </summary>
/// <param name="mediaId"></param>
/// <param name="filePath">
/// 保存下载的文件的本地文件名或目录(以\结尾)。
/// 如果为目录，则文件名为微信响应的文件名。
/// 如果文件已经存在，则会覆盖原文件。
/// </param>
/// <returns>如果成功，ErrMsg属性携带保存的文件全路径</returns>
public BasicResult Download(string mediaId, string filePath)
{
var param = new FormData
{
{ "access_token", AccessToken },
{ "media_id", mediaId }
};
var url = string.Format("{0}?{1}", DownLoadUrl, param.Format());
var request = HttpHelper.CreateRequest(url);
var response = request.GetResponse();
using (var stream = response.GetResponseStream())
{
var disposition = response.Headers["Content-disposition"];
if (string.IsNullOrEmpty(disposition))
{
var s = new StreamReader(stream, Encoding.UTF8).ReadToEnd();
return(JsonConvert.DeserializeObject <BasicResult>(s));
}
filePath = filePath.EndsWith(@"\")
? string.Format("{0}{1}", filePath,
Regex.Match(disposition, "(?<=filename\\s*=\\s*\\\"?)[^\\\"]+", RegexOptions.IgnoreCase))
: filePath;
var fs = new FileStream(filePath, FileMode.OpenOrCreate);
try
{
var buffer = new byte[128 * 1024]; //128K
int i;
while ((i = stream.Read(buffer, 0, buffer.Length)) > 0)
{
fs.Write(buffer, 0, i);
}
return(BasicResult.GetSuccess(filePath));
}
finally
{
fs.Close();
}
}
}