支持缩略图，是否等比缩放，指定像素缩放，限定上传大小，上传尺寸，图片存放路径，信息导出
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.Drawing;
using System.IO;
/// <summary>
/// UploadIMG 的摘要说明
/// </summary>
public class UploadIMG
{
public UploadIMG()
{
//
// TODO: 在此处添加构造函数逻辑
//
}
private string _MSG;
private string _ofullname;
private string _tfullname;
private string _ofilename;
private string _tfilename;
private int _limitwidth = 2048;
private int _limitheight = 1536;
private int _twidth = 100;
private int _theight = 100;
private int _size = 1000000;
private bool _israte = true;
private string _path = "UpdateFile";
/// <summary>
/// 信息
/// </summary>
public string MSG
{
get { return _MSG; }
set { _MSG = value; }
}
/// <summary>
/// 保存时的完整路径.原图
/// </summary>
public string OFullName
{
get { return _ofullname; }
set { _ofullname = value; }
}
/// <summary>
/// 保存时的完整路径.缩略图
/// </summary>
public string TFullName
{
get { return _tfullname; }
set { _tfullname = value; }
}
/// <summary>
/// 保存时的图片名称.原图
/// </summary>
public string OFileName
{
get { return _ofilename; }
set { _ofilename = value; }
}
/// <summary>
/// 保存时的图片名称.缩略图
/// </summary>
public string TFileName
{
get { return _tfilename; }
set { _tfilename = value; }
}
/// <summary>
/// 限定宽度
/// </summary>
public int LimitWidth
{
get { return _limitwidth; }
set { _limitwidth = value; }
}
/// <summary>
/// 限定高度
/// </summary>
public int LimitHeight
{
get { return _limitheight; }
set { _limitheight = value; }
}
/// <summary>
/// 缩略图宽度
/// </summary>
public int TWidth
{
get { return _twidth; }
set { _twidth = value; }
}
/// <summary>
/// 缩略图高度
/// </summary>
public int THeight
{
get { return _theight; }
set { _theight = value; }
}
/// <summary>
/// 文件大小
/// </summary>
public int Size
{
get { return _size; }
set { _size = value; }
}
/// <summary>
/// 是否成比例
/// </summary>
public bool IsRate
{
get { return _israte; }
set { _israte = value; }
}
/// <summary>
/// 存放图片的文件夹名称
/// </summary>
public string Path
{
get { return _path; }
set { _path = value; }
}
/// <summary>
/// 图片上传(默认:"等比压缩,限定上传尺寸2048*1536,缩略图尺寸100*100,限定上传大小1MB,存放在根目录UpdateFile中")
/// </summary>
/// <param name="UploadFile">文件上传控件</param>
/// <returns>返回是否成功保存图片</returns>
public bool UpLoadIMG(FileUpload UploadFile)
{
if (UploadFile.HasFile)//检查是否已经选择文件
{
string filename = UploadFile.FileName.ToLower();
int i = filename.LastIndexOf(".");
filename = filename.Substring(i, filename.Length - i);
if (!(filename == ".jpg" || filename == ".jpeg" || filename == ".gif" || filename == ".png" || filename == ".bmp"))
{
MSG = "不受支持的类型,请重新选择!";
return false;
}//检查上传文件的格式是否有效
if (UploadFile.PostedFile.ContentLength == 0 || UploadFile.PostedFile.ContentLength >= Size)
{
MSG = "指定的文件大小不符合要求!";
return false;
}//检查图片文件的大小
//生成原图
Stream oStream = UploadFile.PostedFile.InputStream;
System.Drawing.Image oImage = System.Drawing.Image.FromStream(oStream);
int owidth = oImage.Width; //原图宽度
int oheight = oImage.Height; //原图高度
if (owidth > LimitWidth || oheight > LimitHeight)
{
MSG = "超过允许的图片尺寸范围!";
return false;
}//检查是否超出规定尺寸
if (IsRate)
{
//按比例计算出缩略图的宽度和高度
if (owidth >= oheight)
{
THeight = (int)Math.Floor(Convert.ToDouble(oheight) * (Convert.ToDouble(TWidth) / Convert.ToDouble(owidth)));//等比设定高度
}
else
{
TWidth = (int)Math.Floor(Convert.ToDouble(owidth) * (Convert.ToDouble(THeight) / Convert.ToDouble(oheight)));//等比设定宽度
}
}
//生成缩略原图
Bitmap tImage = new Bitmap(TWidth, THeight);
Graphics g = Graphics.FromImage(tImage);
g.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.High; //设置高质量插值法
g.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality;//设置高质量,低速度呈现平滑程度
g.Clear(Color.Transparent); //清空画布并以透明背景色填充
g.DrawImage(oImage, new Rectangle(0, 0, TWidth, THeight), new Rectangle(0, 0, owidth, oheight), GraphicsUnit.Pixel);
Random oRandom = new Random();
string oStringRandom = oRandom.Next(9999).ToString();//生成4位随机数字
//格式化日期作为文件名
DateTime oDateTime = new DateTime();
oDateTime = DateTime.Now;
string oStringTime = oDateTime.ToString();
oStringTime = oStringTime.Replace("-", "");
oStringTime = oStringTime.Replace(" ", "");
oStringTime = oStringTime.Replace(":", "");
OFileName = "o" + oStringTime + oStringRandom + filename;
TFileName = "t" + oStringTime + oStringRandom + filename;
string oSavePath = HttpContext.Current.Server.MapPath("~") + "\\"+Path+"\\";
if (!Directory.Exists(oSavePath))
{
Directory.CreateDirectory(oSavePath);//在根目录下建立文件夹
}
//保存路径+完整文件名
OFullName = oSavePath + OFileName;
TFullName = oSavePath + TFileName;
//开始保存图片至服务器
try
{
switch (filename)
{
case ".jpeg":
case ".jpg":
{
oImage.Save(OFullName, System.Drawing.Imaging.ImageFormat.Jpeg);
tImage.Save(TFullName, System.Drawing.Imaging.ImageFormat.Jpeg);
break;
}
case ".gif":
{
oImage.Save(OFullName, System.Drawing.Imaging.ImageFormat.Gif);
tImage.Save(TFullName, System.Drawing.Imaging.ImageFormat.Gif);
break;
}
case ".png":
{
oImage.Save(OFullName, System.Drawing.Imaging.ImageFormat.Png);
tImage.Save(TFullName, System.Drawing.Imaging.ImageFormat.Png);
break;
}
case ".bmp":
{
oImage.Save(OFullName, System.Drawing.Imaging.ImageFormat.Bmp);
tImage.Save(TFullName, System.Drawing.Imaging.ImageFormat.Bmp);
break;
}
}
MSG = "图片上传成功!";
return true;
}
catch (Exception ex)
{
MSG = ex.Message;
return false;
}
finally
{
//释放资源
oImage.Dispose();
g.Dispose();
tImage.Dispose();
}
}
else
{
MSG = "请先选择需要上传的图片!";
return false;
}
}
}
-----------------------------------------------------------
调用:
只要先实例化类之后，设置想要的属性。
UpLoadIMG（this.fileupload1）
输入文件上传控件的ID作为参数就可以了。
属性：
1.原始图片完整路径
2.原始图片名称
3.缩略图完整路径
4.缩略图名称
5.限定宽度
6.限定高度
7.缩略图宽度
8.缩略图高度
9.限定大小
10.是否等比压缩
11.存放路径
12.信息输出
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