public void ProcessRequest(HttpContext context)
{
string fileIdentity = context.Request.QueryString["FileIdentity"];
if (fileIdentity == null || fileIdentity.Trim().Length <= 0)
{
throw new ApplicationException("There is no 'FileIdentity'.");
}
fileIdentity = Encoding.UTF8.GetString(Convert.FromBase64String(fileIdentity));
if (context.Request.QueryString["Action"] == "cancel")
{
FileUploadManager.DeleteFile(fileIdentity);
return;
}
long startPosition = 0;
string startStr = context.Request.QueryString["StartPosition"];
if (startStr == null || startStr.Trim().Length <= 0 || !long.TryParse(startStr, out startPosition) || startPosition < 0)
{
throw new ApplicationException("There is no 'StartPosition' or 'StartPosition' is invalid.");
}
string filePath = Path.Combine(FileUploadManager.BaseFolder, fileIdentity);
string folderPath = Path.GetDirectoryName(filePath);
if (!Directory.Exists(folderPath))
{
Directory.CreateDirectory(folderPath);
}
Stream stream = context.Request.InputStream;
using (FileStream fs = new FileStream(filePath, FileMode.OpenOrCreate, FileAccess.Write, FileShare.Write))
{
fs.Seek(startPosition, SeekOrigin.Begin);
byte[] buffer = new byte[4096];
int bytesRead;
while ((bytesRead = stream.Read(buffer, 0, buffer.Length)) != 0)
{
fs.Write(buffer, 0, bytesRead);
}
fs.Close();
}
context.Response.Write(fileIdentity);
}
/// <summary>
///是否为图片
/// </summary>
/// <param name="fileIdentity"></param>
public static bool IsImages(string fileIdentity)
{
var result = FileUploadManager.FileExists(fileIdentity);
if (!result)
{
return(false);
}
var curentByte = FileUploadManager.GetFileData(fileIdentity, 0, 3);
if (curentByte.Length < 3)
{
return(false);
}
//读取文件前三个字节确定文件后缀
var fileType = curentByte[0].ToString() + curentByte[1].ToString() + curentByte[2].ToString();
return(fileType.Contains(JPG.ToString()));
}