using System;
using System.Data;
using System.Configuration;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
using System.IO;

///

/// Summary description for UploadFile
///

public class UploadFile
{
private string[] AllowFileType; //所允许的文件类型
private double FileLength; //所允许的文件大小(KB)
private string SavePath; //文件的存储路径
private string SaveFile; //上传后的文件名
private string Error; //存储错误信息
private string FileExtesion; //上传文件的扩展名

///

/// 构造函数
///

/// 允许的文件类型，多个以","分开
/// 文件大小
/// 保存路径
public UploadFile(string allFileType, double fileLength, string savePath)
{
char[] sp = { ',' };
AllowFileType = allFileType.Split(sp);
FileLength = fileLength * 1024;
SavePath = savePath;
}

///

/// 返回生成的文件名
///

public string FileName
{
get
{
return SaveFile;
}
}

///

/// 返回出错信息
///

public string ErrorMessage
{
get
{
return Error;
}
}

///

/// 根据SavePath,生成文件名
///

///
private string MakeFileName(string fileType,string fileName)
{
string file = this.SavePath + "\\" + DateTime.Now.ToString("yyMMddhhmmss") + fileName;
while (File.Exists(file))
{
file = this.SavePath + "\\" + DateTime.Now.ToString("yyMMddhhmmss") + fileName;
}
return file;
}

///

/// 检查文件类型
///

/// MIME内容
///
private bool CheckFileExt(string fileEx)
{
bool result = false;
for (int i = 0; i < this.AllowFileType.Length; i++)
{
if (fileEx.IndexOf(this.AllowFileType[i].ToLower()) > -1)
{
result = true;
break;
}
}
return result;
}

public bool UpLoad(System.Web.UI.WebControls.FileUpload file)
{
bool result = true;
try
{
//查看文件长度
if (file.PostedFile.ContentLength > (this.FileLength))
{
this.Error = "文件大小超出范允许的范围！";
return false;
}

string fileName = Path.GetFileName(file.PostedFile.FileName);
this.FileExtesion = Path.GetExtension(fileName);

if (!CheckFileExt(this.FileExtesion.ToLower()))
{
this.Error = "文件类型" + this.FileExtesion + "不允许！";
return false;
}
//取得要保存的文件名
string UpFile = this.MakeFileName(this.FileExtesion, fileName);
//保存文件
file.PostedFile.SaveAs(UpFile);

//返回文件名
this.SaveFile = Path.GetFileName(UpFile);

}
catch (Exception e)
{
result = false;
this.Error = e.Message;
}
return result;
}

}