这篇文章主要介绍了ASP NET简单好用功能齐全图片上传工具类（水印、缩略图、裁剪等），在开发过程应该对大家很有帮助，小编结合实例代码给大家介绍的非常详细，需要的朋友可以参考下
使用方法：
UploadImage ui = new UploadImage();
/***可选参数***/
ui.SetWordWater = "哈哈";//文字水印
// ui.SetPicWater = Server.MapPath("2.png");//图片水印(图片和文字都赋值图片有效)
ui.SetPositionWater = 4;//水印图片的位置 0居中、1左上角、2右上角、3左下角、4右下角
ui.SetSmallImgHeight = "110,40,20";//设置缩略图可以多个
ui.SetSmallImgWidth = "100,40,20";
//保存图片生成缩略图
var reponseMessage = ui.FileSaveAs(Request.Files[0], Server.MapPath("~/file/temp"));
//裁剪图片
var reponseMessage2 = ui.FileCutSaveAs(Request.Files[0], Server.MapPath("~/file/temp2"), 400, 300, UploadImage.CutMode.CutNo);
/***返回信息***/
var isError = reponseMessage.IsError;//是否异常
var webPath = reponseMessage.WebPath;//web路径
var filePath = reponseMessage.filePath;//物理路径
var message = reponseMessage.Message;//错误信息
var directory = reponseMessage.Directory;//目录
var smallPath1 = reponseMessage.SmallPath(0);//缩略图路径1
var smallPath2 = reponseMessage.SmallPath(1);//缩略图路径2
var smallPath3 = reponseMessage.SmallPath(2);//缩略图路径3
效果：
源码：
using System;
using System.Collections.Generic;
using System.Text;
using System.IO;
using System.Web;
using System.Drawing;
using System.Drawing.Imaging;
using System.Drawing.Drawing2D;
using System.Collections;
using System.Net;
using System.Text.RegularExpressions;
using System.Configuration;
namespace SyntacticSugar
{
/// <summary>
/// ** 描述：图片上传类、支持水印、缩略图
/// ** 创始时间：2015-5-28
/// ** 修改时间：-
/// ** 修改人：sunkaixuan
/// </summary>
public class UploadImage
{
#region 属性
/// <summary>
/// 允许图片格式
/// </summary>
public string SetAllowFormat { get; set; }
/// <summary>
/// 允许上传图片大小
/// </summary>
public double SetAllowSize { get; set; }
/// <summary>
/// 文字水印字符
/// </summary>
public string SetWordWater { get; set; }
/// <summary>
/// 图片水印
/// </summary>
public string SetPicWater { get; set; }
/// <summary>
/// 水印图片的位置 0居中、1左上角、2右上角、3左下角、4右下角
/// </summary>
public int SetPositionWater { get; set; }
/// <summary>
/// 缩略图宽度多个逗号格开（例如:200,100）
/// </summary>
public string SetSmallImgWidth { get; set; }
/// <summary>
/// 缩略图高度多个逗号格开（例如:200,100）
/// </summary>
public string SetSmallImgHeight { get; set; }
/// <summary>
/// 是否限制最大宽度，默认为true
/// </summary>
public bool SetLimitWidth { get; set; }
/// <summary>
/// 最大宽度尺寸，默认为600
/// </summary>
public int SetMaxWidth { get; set; }
/// <summary>
/// 是否剪裁图片，默认true
/// </summary>
public bool SetCutImage { get; set; }
/// <summary>
/// 限制图片最小宽度，0表示不限制
/// </summary>
public int SetMinWidth { get; set; }
#endregion
public UploadImage()
{
SetAllowFormat = ".jpeg|.jpg|.bmp|.gif|.png"; //允许图片格式
SetAllowSize = 1; //允许上传图片大小,默认为1MB
SetPositionWater = 4;
SetCutImage = true;
}
#region main method
/// <summary>
/// 裁剪图片
/// </summary>
/// <param name="PostedFile">HttpPostedFile控件</param>
/// <param name="SavePath">保存路径【sys.config配置路径】</param>
/// <param name="oImgWidth">图片宽度</param>
/// <param name="oImgHeight">图片高度</param>
/// <param name="cMode">剪切类型</param>
/// <param name="ext">返回格式</param>
/// <returns>返回上传信息</returns>
public ResponseMessage FileCutSaveAs(System.Web.HttpPostedFile PostedFile, string SavePath, int oImgWidth, int oImgHeight, CutMode cMode)
{
ResponseMessage rm = new ResponseMessage();
try
{
//获取上传文件的扩展名
string sEx = System.IO.Path.GetExtension(PostedFile.FileName);
if (!CheckValidExt(SetAllowFormat, sEx))
{
TryError(rm, 2);
return rm;
}
//获取上传文件的大小
double PostFileSize = PostedFile.ContentLength / 1024.0 / 1024.0;
if (PostFileSize > SetAllowSize)
{
TryError(rm, 3);
return rm; //超过文件上传大小
}
if (!System.IO.Directory.Exists(SavePath))
{
System.IO.Directory.CreateDirectory(SavePath);
}
//重命名名称
string NewfileName = DateTime.Now.Year.ToString() + DateTime.Now.Month.ToString() + DateTime.Now.Day.ToString() + DateTime.Now.Hour.ToString() + DateTime.Now.Minute.ToString() + DateTime.Now.Second.ToString() + DateTime.Now.Millisecond.ToString("000");
string fName = "s" + NewfileName + sEx;
string fullPath = Path.Combine(SavePath, fName);
PostedFile.SaveAs(fullPath);
//重命名名称
string sNewfileName = DateTime.Now.Year.ToString() + DateTime.Now.Month.ToString() + DateTime.Now.Day.ToString() + DateTime.Now.Hour.ToString() + DateTime.Now.Minute.ToString() + DateTime.Now.Second.ToString() + DateTime.Now.Millisecond.ToString("000");
string sFName = sNewfileName + sEx;
rm.IsError = false;
rm.FileName = sFName;
string sFullPath = Path.Combine(SavePath, sFName);
rm.filePath = sFullPath;
rm.WebPath = "/"+sFullPath.Replace(HttpContext.Current.Server.MapPath("~/"), "").Replace("\\", "/");
CreateSmallPhoto(fullPath, oImgWidth, oImgHeight, sFullPath, SetPicWater, SetWordWater, cMode);
if (File.Exists(fullPath))
{
File.Delete(fullPath);
}
//压缩
if (PostFileSize > 100)
{
CompressPhoto(sFullPath, 100);
}
}
catch (Exception ex)
{
TryError(rm, ex.Message);
}
return rm;
}
/// <summary>
/// 通用图片上传类
/// </summary>
/// <param name="PostedFile">HttpPostedFile控件</param>
/// <param name="SavePath">保存路径【sys.config配置路径】</param>
/// <param name="finame">返回文件名</param>
/// <param name="fisize">返回文件大小</param>
/// <returns>返回上传信息</returns>
public ResponseMessage FileSaveAs(System.Web.HttpPostedFile PostedFile, string SavePath)
{
ResponseMessage rm = new ResponseMessage();
try
{
if (string.IsNullOrEmpty(PostedFile.FileName))
{
TryError(rm, 4);
return rm;
}
Random rd = new Random();
int rdInt = rd.Next(1000, 9999);
//重命名名称
string NewfileName = DateTime.Now.Year.ToString() + DateTime.Now.Month.ToString() + DateTime.Now.Day.ToString() + DateTime.Now.Hour.ToString() + DateTime.Now.Minute.ToString() + DateTime.Now.Second.ToString() + DateTime.Now.Millisecond.ToString() + rdInt;
//获取上传文件的扩展名
string sEx = System.IO.Path.GetExtension(PostedFile.FileName);
if (!CheckValidExt(SetAllowFormat, sEx))
{
TryError(rm, 2);
return rm;
}
//获取上传文件的大小
double PostFileSize = PostedFile.ContentLength / 1024.0 / 1024.0;
if (PostFileSize > SetAllowSize)
{
TryError(rm, 3);
return rm;
}
if (!System.IO.Directory.Exists(SavePath))
{
System.IO.Directory.CreateDirectory(SavePath);
}
rm.FileName = NewfileName + sEx;
string fullPath = SavePath.Trim('\\') + "\\" + rm.FileName;
rm.WebPath = "/"+fullPath.Replace(HttpContext.Current.Server.MapPath("~/"), "").Replace("\\", "/");
rm.filePath = fullPath;
rm.Size = PostFileSize;
PostedFile.SaveAs(fullPath);
System.Drawing.Bitmap bmp = new Bitmap(fullPath);
int realWidth = bmp.Width;
int realHeight = bmp.Height;
bmp.Dispose();
#region 检测图片宽度限制
if (SetMinWidth > 0)
{
if (realWidth < SetMinWidth)
{
TryError(rm, 7);
return rm;
}
}
#endregion
#region 监测图片宽度是否超过600，超过的话，自动压缩到600
if (SetLimitWidth && realWidth > SetMaxWidth)
{
int mWidth = SetMaxWidth;
int mHeight = mWidth * realHeight / realWidth;
string tempFile = SavePath + Guid.NewGuid().ToString() + sEx;
File.Move(fullPath, tempFile);
CreateSmallPhoto(tempFile, mWidth, mHeight, fullPath, "", "");
File.Delete(tempFile);
}
#endregion
#region 压缩图片存储尺寸
if (sEx.ToLower() != ".gif")
{
CompressPhoto(fullPath, 100);
}
#endregion
//生成缩略图片高宽
if (string.IsNullOrEmpty(SetSmallImgWidth))
{
rm.Message = "上传成功,无缩略图";
return rm;
}
string[] oWidthArray = SetSmallImgWidth.Split(',');
string[] oHeightArray = SetSmallImgHeight.Split(',');
if (oWidthArray.Length != oHeightArray.Length)
{
TryError(rm, 6);
return rm;
}
for (int i = 0; i < oWidthArray.Length; i++)
{
if (Convert.ToInt32(oWidthArray[i]) <= 0 || Convert.ToInt32(oHeightArray[i]) <= 0)
continue;
string sImg = SavePath.TrimEnd('\\') + '\\' + NewfileName + "_" + i.ToString() + sEx;
//判断图片高宽是否大于生成高宽。否则用原图
if (realWidth > Convert.ToInt32(oWidthArray[i]))
{
if (SetCutImage)
CreateSmallPhoto(fullPath, Convert.ToInt32(oWidthArray[i]), Convert.ToInt32(oHeightArray[i]), sImg, "", "");
else
CreateSmallPhoto(fullPath, Convert.ToInt32(oWidthArray[i]), Convert.ToInt32(oHeightArray[i]), sImg, "", "", CutMode.CutNo);
}
else
{
if (SetCutImage)
CreateSmallPhoto(fullPath, realWidth, realHeight, sImg, "", "");
else
CreateSmallPhoto(fullPath, realWidth, realHeight, sImg, "", "", CutMode.CutNo);
}
}
#region 给大图添加水印
if (!string.IsNullOrEmpty(SetPicWater))
AttachPng(SetPicWater, fullPath);
else if (!string.IsNullOrEmpty(SetWordWater))
AttachText(SetWordWater, fullPath);
#endregion
}
catch (Exception ex)
{
TryError(rm, ex.Message);
}
return rm;
}
#region 验证格式
/// <summary>
/// 验证格式
/// </summary>
/// <param name="allType">所有格式</param>
/// <param name="chkType">被检查的格式</param>
/// <returns>bool</returns>
public bool CheckValidExt(string allType, string chkType)
{
bool flag = false;
string[] sArray = allType.Split('|');
foreach (string temp in sArray)
{
if (temp.ToLower() == chkType.ToLower())
{
flag = true;
break;
}
}
return flag;
}
#endregion
#region 根据需要的图片尺寸，按比例剪裁原始图片
/// <summary>
/// 根据需要的图片尺寸，按比例剪裁原始图片
/// </summary>
/// <param name="nWidth">缩略图宽度</param>
/// <param name="nHeight">缩略图高度</param>
/// <param name="img">原始图片</param>
/// <returns>剪裁区域尺寸</returns>
public Size CutRegion(int nWidth, int nHeight, Image img)
{
double width = 0.0;
double height = 0.0;
double nw = (double)nWidth;
double nh = (double)nHeight;
double pw = (double)img.Width;
double ph = (double)img.Height;
if (nw / nh > pw / ph)
{
width = pw;
height = pw * nh / nw;
}
else if (nw / nh < pw / ph)
{
width = ph * nw / nh;
height = ph;
}
else
{
width = pw;
height = ph;
}
return new Size(Convert.ToInt32(width), Convert.ToInt32(height));
}
#endregion
#region 等比例缩小图片
public Size NewSize(int nWidth, int nHeight, Image img)
{
double w = 0.0;
double h = 0.0;
double sw = Convert.ToDouble(img.Width);
double sh = Convert.ToDouble(img.Height);
double mw = Convert.ToDouble(nWidth);
double mh = Convert.ToDouble(nHeight);
if (sw < mw && sh < mh)
{
w = sw;
h = sh;
}
else if ((sw / sh) > (mw / mh))
{
w = nWidth;
h = (w * sh) / sw;
}
else
{
h = nHeight;
w = (h * sw) / sh;
}
return new Size(Convert.ToInt32(w), Convert.ToInt32(h));
}
#endregion
#region 生成缩略图
#region 生成缩略图，不加水印
/// <summary>
/// 生成缩略图，不加水印
/// </summary>
/// <param name="filename">源文件</param>
/// <param name="nWidth">缩略图宽度</param>
/// <param name="nHeight">缩略图高度</param>
/// <param name="destfile">缩略图保存位置</param>
public void CreateSmallPhoto(string filename, int nWidth, int nHeight, string destfile)
{
Image img = Image.FromFile(filename);
ImageFormat thisFormat = img.RawFormat;
Size CutSize = CutRegion(nWidth, nHeight, img);
Bitmap outBmp = new Bitmap(nWidth, nHeight);
Graphics g = Graphics.FromImage(outBmp);
// 设置画布的描绘质量
g.CompositingQuality = CompositingQuality.HighQuality;
g.SmoothingMode = SmoothingMode.HighQuality;
g.InterpolationMode = InterpolationMode.HighQualityBicubic;
int nStartX = (img.Width - CutSize.Width) / 2;
int nStartY = (img.Height - CutSize.Height) / 2;
g.DrawImage(img, new Rectangle(0, 0, nWidth, nHeight),
nStartX, nStartY, CutSize.Width, CutSize.Height, GraphicsUnit.Pixel);
g.Dispose();
//if (thisFormat.Equals(ImageFormat.Gif))
//{
// Response.ContentType = "image/gif";
//}
//else
//{
// Response.ContentType = "image/jpeg";
//}
// 以下代码为保存图片时，设置压缩质量
EncoderParameters encoderParams = new EncoderParameters();
long[] quality = new long[1];
quality[0] = 100;
EncoderParameter encoderParam = new EncoderParameter(System.Drawing.Imaging.Encoder.Quality, quality);
encoderParams.Param[0] = encoderParam;
//获得包含有关内置图像编码解码器的信息的ImageCodecInfo 对象。
ImageCodecInfo[] arrayICI = ImageCodecInfo.GetImageEncoders();
ImageCodecInfo jpegICI = null;
for (int x = 0; x < arrayICI.Length; x++)
{
if (arrayICI[x].FormatDescription.Equals("JPEG"))
{
jpegICI = arrayICI[x];//设置JPEG编码
break;
}
}
if (jpegICI != null)
{
//outBmp.Save(Response.OutputStream, jpegICI, encoderParams);
outBmp.Save(destfile, jpegICI, encoderParams);
}
else
{
//outBmp.Save(Response.OutputStream, thisFormat);
outBmp.Save(destfile, thisFormat);
}
img.Dispose();
outBmp.Dispose();
}
#endregion
#region 生成缩略图，加水印
public void CreateSmallPhoto(string filename, int nWidth, int nHeight, string destfile, string sy, int nType)
{
if (nType == 0)
CreateSmallPhoto(filename, nWidth, nHeight, destfile, sy, "");
else
CreateSmallPhoto(filename, nWidth, nHeight, destfile, "", sy);
}
#endregion
#region 生成缩略图
/// <summary>
/// 生成缩略图
/// </summary>
/// <param name="filename">源文件</param>
/// <param name="nWidth">缩略图宽度</param>
/// <param name="nHeight">缩略图高度</param>
/// <param name="destfile">缩略图保存位置</param>
/// <param name="png">图片水印</param>
/// <param name="text">文本水印</param>
public void CreateSmallPhoto(string filename, int nWidth, int nHeight, string destfile, string png, string text)
{
Image img = Image.FromFile(filename);
ImageFormat thisFormat = img.RawFormat;
Size CutSize = CutRegion(nWidth, nHeight, img);
Bitmap outBmp = new Bitmap(nWidth, nHeight);
Graphics g = Graphics.FromImage(outBmp);
g.Clear(Color.White);
// 设置画布的描绘质量
g.CompositingQuality = CompositingQuality.HighQuality;
g.SmoothingMode = SmoothingMode.HighQuality;
g.InterpolationMode = InterpolationMode.HighQualityBicubic;
int nStartX = (img.Width - CutSize.Width) / 2;
int nStartY = (img.Height - CutSize.Height) / 2;
g.DrawImage(img, new Rectangle(0, 0, nWidth, nHeight),
nStartX, nStartY, CutSize.Width, CutSize.Height, GraphicsUnit.Pixel);
g.Dispose();
// 以下代码为保存图片时，设置压缩质量
EncoderParameters encoderParams = new EncoderParameters();
long[] quality = new long[1];
quality[0] = 100;
EncoderParameter encoderParam = new EncoderParameter(System.Drawing.Imaging.Encoder.Quality, quality);
encoderParams.Param[0] = encoderParam;
//获得包含有关内置图像编码解码器的信息的ImageCodecInfo 对象。
ImageCodecInfo[] arrayICI = ImageCodecInfo.GetImageEncoders();
ImageCodecInfo jpegICI = null;
for (int x = 0; x < arrayICI.Length; x++)
{
if (arrayICI[x].FormatDescription.Equals("JPEG"))
{
jpegICI = arrayICI[x];//设置JPEG编码
break;
}
}
if (jpegICI != null)
{
outBmp.Save(destfile, jpegICI, encoderParams);
}
else
{
outBmp.Save(destfile, thisFormat);
}
img.Dispose();
outBmp.Dispose();
if (!string.IsNullOrEmpty(png))
AttachPng(png, destfile);
if (!string.IsNullOrEmpty(text))
AttachText(text, destfile);
}
public void CreateSmallPhoto(string filename, int nWidth, int nHeight, string destfile, string png, string text, CutMode cMode)
{
Image img = Image.FromFile(filename);
if (nWidth <= 0)
nWidth = img.Width;
if (nHeight <= 0)
nHeight = img.Height;
int towidth = nWidth;
int toheight = nHeight;
switch (cMode)
{
case CutMode.CutWH://指定高宽缩放（可能变形）
break;
case CutMode.CutW://指定宽，高按比例
toheight = img.Height * nWidth / img.Width;
break;
case CutMode.CutH://指定高，宽按比例
towidth = img.Width * nHeight / img.Height;
break;
case CutMode.CutNo: //缩放不剪裁
int maxSize = (nWidth >= nHeight ? nWidth : nHeight);
if (img.Width >= img.Height)
{
towidth = maxSize;
toheight = img.Height * maxSize / img.Width;
}
else
{
toheight = maxSize;
towidth = img.Width * maxSize / img.Height;
}
break;
default:
break;
}
nWidth = towidth;
nHeight = toheight;
ImageFormat thisFormat = img.RawFormat;
Size CutSize = new Size(nWidth, nHeight);
if (cMode != CutMode.CutNo)
CutSize = CutRegion(nWidth, nHeight, img);
Bitmap outBmp = new Bitmap(CutSize.Width, CutSize.Height);
Graphics g = Graphics.FromImage(outBmp);
g.Clear(Color.White);
// 设置画布的描绘质量
g.CompositingQuality = CompositingQuality.HighQuality;
g.SmoothingMode = SmoothingMode.HighQuality;
g.InterpolationMode = InterpolationMode.HighQualityBicubic;
int nStartX = (img.Width - CutSize.Width) / 2;
int nStartY = (img.Height - CutSize.Height) / 2;
//int x1 = (outBmp.Width - nWidth) / 2;
//int y1 = (outBmp.Height - nHeight) / 2;
if (cMode != CutMode.CutNo)
g.DrawImage(img, new Rectangle(0, 0, nWidth, nHeight),
nStartX, nStartY, CutSize.Width, CutSize.Height, GraphicsUnit.Pixel);
else
g.DrawImage(img, new Rectangle(0, 0, nWidth, nHeight),
0, 0, img.Width, img.Height, GraphicsUnit.Pixel);
g.Dispose();
// 以下代码为保存图片时，设置压缩质量
EncoderParameters encoderParams = new EncoderParameters();
long[] quality = new long[1];
quality[0] = 100;
EncoderParameter encoderParam = new EncoderParameter(System.Drawing.Imaging.Encoder.Quality, quality);
encoderParams.Param[0] = encoderParam;
//获得包含有关内置图像编码解码器的信息的ImageCodecInfo 对象。
ImageCodecInfo[] arrayICI = ImageCodecInfo.GetImageEncoders();
ImageCodecInfo jpegICI = null;
for (int x = 0; x < arrayICI.Length; x++)
{
if (arrayICI[x].FormatDescription.Equals("JPEG"))
{
jpegICI = arrayICI[x];//设置JPEG编码
break;
}
}
if (jpegICI != null)
{
outBmp.Save(destfile, jpegICI, encoderParams);
}
else
{
outBmp.Save(destfile, thisFormat);
}
img.Dispose();
outBmp.Dispose();
if (!string.IsNullOrEmpty(png))
AttachPng(png, destfile);
if (!string.IsNullOrEmpty(text))
AttachText(text, destfile);
}
#endregion
#endregion
#region 添加文字水印
public void AttachText(string text, string file)
{
if (string.IsNullOrEmpty(text))
return;
if (!System.IO.File.Exists(file))
return;
System.IO.FileInfo oFile = new System.IO.FileInfo(file);
string strTempFile = System.IO.Path.Combine(oFile.DirectoryName, Guid.NewGuid().ToString() + oFile.Extension);
oFile.CopyTo(strTempFile);
Image img = Image.FromFile(strTempFile);
ImageFormat thisFormat = img.RawFormat;
int nHeight = img.Height;
int nWidth = img.Width;
Bitmap outBmp = new Bitmap(nWidth, nHeight);
Graphics g = Graphics.FromImage(outBmp);
g.Clear(Color.White);
// 设置画布的描绘质量
g.CompositingQuality = CompositingQuality.HighQuality;
g.SmoothingMode = SmoothingMode.HighQuality;
g.InterpolationMode = InterpolationMode.HighQualityBicubic;
g.DrawImage(img, new Rectangle(0, 0, nWidth, nHeight),
0, 0, nWidth, nHeight, GraphicsUnit.Pixel);
int[] sizes = new int[] { 16, 14, 12, 10, 8, 6, 4 };
Font crFont = null;
SizeF crSize = new SizeF();
//通过循环这个数组，来选用不同的字体大小
//如果它的大小小于图像的宽度，就选用这个大小的字体
for (int i = 0; i < 7; i++)
{
//设置字体，这里是用arial，黑体
crFont = new Font("arial", sizes[i], FontStyle.Bold);
//Measure the Copyright string in this Font
crSize = g.MeasureString(text, crFont);
if ((ushort)crSize.Width < (ushort)nWidth)
break;
}
//因为图片的高度可能不尽相同, 所以定义了
//从图片底部算起预留了5%的空间
int yPixlesFromBottom = (int)(nHeight * .08);
//现在使用版权信息字符串的高度来确定要绘制的图像的字符串的y坐标
float yPosFromBottom = ((nHeight - yPixlesFromBottom) - (crSize.Height / 2));
//计算x坐标
float xCenterOfImg = (nWidth / 2);
//把文本布局设置为居中
StringFormat StrFormat = new StringFormat();
StrFormat.Alignment = StringAlignment.Center;
//通过Brush来设置黑色半透明
SolidBrush semiTransBrush2 = new SolidBrush(Color.FromArgb(153, 0, 0, 0));
//绘制版权字符串
g.DrawString(text, //版权字符串文本
crFont, //字体
semiTransBrush2, //Brush
new PointF(xCenterOfImg + 1, yPosFromBottom + 1), //位置
StrFormat);
//设置成白色半透明
SolidBrush semiTransBrush = new SolidBrush(Color.FromArgb(153, 255, 255, 255));
//第二次绘制版权字符串来创建阴影效果
//记住移动文本的位置1像素
g.DrawString(text, //版权文本
crFont, //字体
semiTransBrush, //Brush
new PointF(xCenterOfImg, yPosFromBottom), //位置
StrFormat);
g.Dispose();
// 以下代码为保存图片时，设置压缩质量
EncoderParameters encoderParams = new EncoderParameters();
long[] quality = new long[1];
quality[0] = 100;
EncoderParameter encoderParam = new EncoderParameter(System.Drawing.Imaging.Encoder.Quality, quality);
encoderParams.Param[0] = encoderParam;
//获得包含有关内置图像编码解码器的信息的ImageCodecInfo 对象。
ImageCodecInfo[] arrayICI = ImageCodecInfo.GetImageEncoders();
ImageCodecInfo jpegICI = null;
for (int x = 0; x < arrayICI.Length; x++)
{
if (arrayICI[x].FormatDescription.Equals("JPEG"))
{
jpegICI = arrayICI[x];//设置JPEG编码
break;
}
}
if (jpegICI != null)
{
outBmp.Save(file, jpegICI, encoderParams);
}
else
{
outBmp.Save(file, thisFormat);
}
img.Dispose();
outBmp.Dispose();
System.IO.File.Delete(strTempFile);
}
#endregion
#region 添加图片水印
///<summary>
/// 添加图片水印
/// </summary>
/// <param name="png">水印图片</param>
/// <param name="file">原文件</param>
/// <param name="position">水印图片的位置 0居中、1左上角、2右上角、3左下角、4右下角</param>
public void AttachPng(string png, string file)
{
if (string.IsNullOrEmpty(png))
return;
if (!System.IO.File.Exists(png))
return;
if (!System.IO.File.Exists(file))
return;
System.IO.FileInfo oFile = new System.IO.FileInfo(file);
string strTempFile = System.IO.Path.Combine(oFile.DirectoryName, Guid.NewGuid().ToString() + oFile.Extension);
oFile.CopyTo(strTempFile);
Image img = Image.FromFile(strTempFile);
ImageFormat thisFormat = img.RawFormat;
int nHeight = img.Height;
int nWidth = img.Width;
Bitmap outBmp = new Bitmap(nWidth, nHeight);
Graphics g = Graphics.FromImage(outBmp);
// 设置画布的描绘质量
g.CompositingQuality = CompositingQuality.HighQuality;
g.SmoothingMode = SmoothingMode.HighQuality;
g.InterpolationMode = InterpolationMode.HighQualityBicubic;
g.DrawImage(img, new Rectangle(0, 0, nWidth, nHeight),
0, 0, nWidth, nHeight, GraphicsUnit.Pixel);
img.Dispose();
img = Image.FromFile(png);
//Bitmap bmpPng = new Bitmap(img);
//ImageAttributes imageAttr = new ImageAttributes();
//Color bg = Color.Green;
//imageAttr.SetColorKey(bg, bg);
Size pngSize = NewSize(nWidth, nHeight, img);
int nx = 0;
int ny = 0;
int padding = 10;
if (SetPositionWater == 0)
{
nx = (nWidth - pngSize.Width) / 2;
ny = (nHeight - pngSize.Height) / 2;
}
else if (SetPositionWater == 1)
{
nx = padding;
ny = padding;
}
else if (SetPositionWater == 2)
{
nx = (nWidth - pngSize.Width) - padding;
ny = padding;
}
else if (SetPositionWater == 3)
{
nx = padding;
ny = (nHeight - pngSize.Height) - padding;
}
else
{
nx = (nWidth - pngSize.Width) - padding;
ny = (nHeight - pngSize.Height) - padding;
}
g.DrawImage(img, new Rectangle(nx, ny, pngSize.Width, pngSize.Height),
0, 0, img.Width, img.Height, GraphicsUnit.Pixel);
g.Dispose();
// 以下代码为保存图片时，设置压缩质量
EncoderParameters encoderParams = new EncoderParameters();
long[] quality = new long[1];
quality[0] = 100;
EncoderParameter encoderParam = new EncoderParameter(System.Drawing.Imaging.Encoder.Quality, quality);
encoderParams.Param[0] = encoderParam;
//获得包含有关内置图像编码解码器的信息的ImageCodecInfo 对象。
ImageCodecInfo[] arrayICI = ImageCodecInfo.GetImageEncoders();
ImageCodecInfo jpegICI = null;
for (int x = 0; x < arrayICI.Length; x++)
{
if (arrayICI[x].FormatDescription.Equals("JPEG"))
{
jpegICI = arrayICI[x];//设置JPEG编码
break;
}
}
if (jpegICI != null)
{
outBmp.Save(file, jpegICI, encoderParams);
}
else
{
outBmp.Save(file, thisFormat);
}
img.Dispose();
outBmp.Dispose();
System.IO.File.Delete(strTempFile);
}
#endregion
#region 得到指定mimeType的ImageCodecInfo
/// <summary>
/// 保存JPG时用
/// </summary>
/// <param name="mimeType"> </param>
/// <returns>得到指定mimeType的ImageCodecInfo </returns>
private ImageCodecInfo GetCodecInfo(string mimeType)
{
ImageCodecInfo[] CodecInfo = ImageCodecInfo.GetImageEncoders();
foreach (ImageCodecInfo ici in CodecInfo)
{
if (ici.MimeType == mimeType) return ici;
}
return null;
}
#endregion
#region 保存为JPEG格式，支持压缩质量选项
/// <summary>
/// 保存为JPEG格式，支持压缩质量选项
/// </summary>
/// <param name="SourceFile"></param>
/// <param name="FileName"></param>
/// <param name="Qty"></param>
/// <returns></returns>
public bool KiSaveAsJPEG(string SourceFile, string FileName, int Qty)
{
Bitmap bmp = new Bitmap(SourceFile);
try
{
EncoderParameter p;
EncoderParameters ps;
ps = new EncoderParameters(1);
p = new EncoderParameter(System.Drawing.Imaging.Encoder.Quality, Qty);
ps.Param[0] = p;
bmp.Save(FileName, GetCodecInfo("image/jpeg"), ps);
bmp.Dispose();
return true;
}
catch
{
bmp.Dispose();
return false;
}
}
#endregion
#region 将图片压缩到指定大小
/// <summary>
/// 将图片压缩到指定大小
/// </summary>
/// <param name="FileName">待压缩图片</param>
/// <param name="size">期望压缩后的尺寸</param>
public void CompressPhoto(string FileName, int size)
{
if (!System.IO.File.Exists(FileName))
return;
int nCount = 0;
System.IO.FileInfo oFile = new System.IO.FileInfo(FileName);
long nLen = oFile.Length;
while (nLen > size * 1024 && nCount < 10)
{
string dir = oFile.Directory.FullName;
string TempFile = System.IO.Path.Combine(dir, Guid.NewGuid().ToString() + "." + oFile.Extension);
oFile.CopyTo(TempFile, true);
KiSaveAsJPEG(TempFile, FileName, 70);
try
{
System.IO.File.Delete(TempFile);
}
catch { }
nCount++;
oFile = new System.IO.FileInfo(FileName);
nLen = oFile.Length;
}
}
#endregion
#endregion
#region common method
/// <summary>
/// 图片上传错误编码
/// </summary>
/// <param name="code"></param>
/// <returns></returns>
private string GetCodeMessage(int code)
{
var dic = new Dictionary<int, string>(){
{0,"系统配置错误"},
{1,"上传图片成功"},
{2,string.Format( "对不起，上传格式错误！请上传{0}格式图片",SetAllowFormat)},
{3,string.Format("超过文件上传大小,不得超过{0}M",SetAllowSize)},
{4,"未上传文件"},
{5,""},
{6,"缩略图长度和宽度配置错误"},
{7,"检测图片宽度限制"}
};
return dic[code];
}
private void TryError(ResponseMessage rm, int code)
{
rm.IsError = true;
rm.Message = GetCodeMessage(code);
}
private void TryError(ResponseMessage rm, string message)
{
rm.IsError = true;
rm.Message = message;
}
#endregion
#region models
public enum CutMode
{
/// <summary>
/// 根据高宽剪切
/// </summary>
CutWH = 1,
/// <summary>
/// 根据宽剪切
/// </summary>
CutW = 2,
/// <summary>
/// 根据高剪切
/// </summary>
CutH = 3,
/// <summary>
/// 缩放不剪裁
/// </summary>
CutNo = 4
}
public class ResponseMessage
{
/// <summary>
/// 是否遇到错误
/// </summary>
public bool IsError { get; set; }
/// <summary>
/// web路径
/// </summary>
public string WebPath { get; set; }
/// <summary>
/// 文件物理路径
/// </summary>
public string filePath { get; set; }
/// <summary>
/// 反回消息
/// </summary>
public string Message { get; set; }
/// <summary>
/// 文件大小
/// </summary>
public double Size { get; set; }
/// <summary>
/// 图片名
/// </summary>
public string FileName { get; set; }
/// <summary>
/// 图片目录
/// </summary>
public string Directory
{
get
{
if (WebPath == null) return null;
return WebPath.Replace(FileName, "");
}
}
/// <summary>
/// 缩略图路径
/// </summary>
public string SmallPath(int index)
{
return string.Format("{0}{1}_{2}{3}", Directory, Path.GetFileNameWithoutExtension(FileName), index, Path.GetExtension(FileName));
}
}
#endregion
}
}
本文ASP.NET简单好用功能齐全图片上传工具类（水印、缩略图、裁剪等）到此结束。蝴蝶需要一次蜕变，才有可能换来惊艳。小编再次感谢大家对我们的支持！
