c# web 多图上传，保存原图，800*800,400*400缩略图
帮助类内容：
1.基本上传图片
2.上传图片(原图上传，自定义路径和名称)
3.上传图片(图片byte[]，自定义路径和名称)
4.上传等比缩放图片
5.给图片加上水印
6.产生图片验证码
7.根据地址获取图片宽和高
8.根据地址获取图片高度
9.图片无损压缩上传
业务源码
引用命名空间
using QuanXi.Web.UI;
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Text;
using System.Web;业务逻辑代码
private void UploadImgs(HttpContext context)
{
HttpFileCollection files = context.Request.Files;
StringBuilder sb = new StringBuilder();
var path = "/uploads/base/photo/" + DateTime.Now.ToString("yyyy") + "/" + DateTime.Now.ToString("MM")+ DateTime.Now.ToString("dd") + "/";
string imgsurl = "",imgurls="",imgurlb="";
if (files.Count <= 0)
{
sb.Append("{\"status\": \"-1\",\"msg\":\"未收到上传图片\"}");
}
else
{
for (int i = 0; i < files.Count; i++)
{
var strPath = path + files[i].FileName;
//files[i].SaveAs(strPath);
HttpPostedFile imgfile = files[i];
//文件真实类型
string strFileType = imgfile.ContentType;
string strFileName = imgfile.FileName;
//文件扩展名
string strFileExtendName = strFileName.Substring(strFileName.LastIndexOf(".") + 1).ToLower();
if (strFileType.StartsWith("image") && (strFileExtendName == "bmp" || strFileExtendName == "jpg" || strFileExtendName == "jpeg" || strFileExtendName == "png" || strFileExtendName == "gif"))
{
//文件大小
long intFileSize = imgfile.ContentLength;
//取当前时间的字符串
string strNowTimeString = 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();
//文件的新名称
string strNewFileName = strNowTimeString + intFileSize.ToString() + "." + strFileExtendName;
//保存原图
AttachmentInfo imgresult = ImageHelper.UploadImage(imgfile, path, strNewFileName);
imgsurl += imgresult.FileUrl + "|";
Stream stmUpload = imgfile.InputStream;
//保存压缩后的小图
Stream sstmUpload = stmUpload;
ImageInfo othumb1 = new ImageInfo();
othumb1.Width = 400;
othumb1.Height = 400;
othumb1.Tag = "s";
string sSaveFile = HttpContext.Current.Server.MapPath(path) + othumb1.Tag + "_" + strNewFileName;
if (ImageHelper.ResizeImage(sstmUpload, sSaveFile, othumb1.Width, othumb1.Height))
{
imgurls += path + othumb1.Tag + "_" + strNewFileName + "|";
}
//sstmUpload.Close();
//sstmUpload.Dispose();
//保存压缩后的大图
Stream bstmUpload = stmUpload;
ImageInfo othumb2 = new ImageInfo();
othumb2.Width = 800;
othumb2.Height = 800;
othumb2.Tag = "b";
string bSaveFile = HttpContext.Current.Server.MapPath(path) + othumb2.Tag + "_" + strNewFileName;
if(ImageHelper.ResizeImage(bstmUpload, bSaveFile, othumb2.Width, othumb2.Height))
{
imgurlb += path + othumb2.Tag + "_" + strNewFileName + "|";
}
stmUpload.Close();
stmUpload.Dispose();
}
}
if (imgsurl.LastIndexOf("|")==imgsurl.Length-1)
{
imgsurl = imgsurl.Substring(0, imgsurl.Length - 1);
}
if (imgurls.LastIndexOf("|") == imgurls.Length-1)
{
imgurls = imgurls.Substring(0,imgurls.Length-1);
}
if (imgurlb.LastIndexOf("|")== imgurlb.Length-1)
{
imgurlb = imgurlb.Substring(0,imgurlb.Length-1);
}
sb.Append("{\"status\": \"0\",\"msg\":\"上传成功\",\"imgsurl\":\""+ imgsurl + "\",\"imgurls\":\"" + imgurls + "\",\"imgurlb\":\"" + imgurlb + "\"}");
}
string strCallBack = RequestProcess.RequestString("callback");
if (strCallBack != "")
{
HttpContext.Current.Response.Write(strCallBack + "(" + sb.ToString() + ");");
HttpContext.Current.Response.End();
}
else
{
HttpContext.Current.Response.Write(sb.ToString());
HttpContext.Current.Response.End();
}
}返回结果
{
"status":"0",
"msg":"上传成功",
"imgsurl":"/uploads/base/photo/2022/0323//2022323953078996789.jpg",
"imgurls":"/uploads/base/photo/2022/0323/s_2022323953078996789.jpg",
"imgurlb":"/uploads/base/photo/2022/0323/b_2022323953078996789.jpg"
}imgsurl：原图
imgurls：压缩后的小图 400*400
imgurlb：压缩后的大图 800*800
图片上传帮助类 ImageHelper.cs
引用命名空间
using System;
using System.Collections.Generic;
using System.Text;
using System.IO;
using System.Drawing;
using System.Web;
using System.Drawing.Imaging;
using System.Drawing.Drawing2D;帮助类 ImageHelper.cs
public class ImageInfo
{
private int m_intWidth = 0;
private int m_intHeight = 0;
private string m_strTag = "";
public int Width
{
set { m_intWidth = value; }
get { return m_intWidth; }
}
public int Height
{
set { m_intHeight = value; }
get { return m_intHeight; }
}
public string Tag
{
set { m_strTag = value; }
get { return m_strTag; }
}
}
public class ImageHelper
{
#region 上传图片
/// <summary>
///
/// </summary>
/// <param name="postedFile">上传过的文件</param>
/// <param name="upLoadForder">分类过的路径</param>
/// <param name="isSaveOriginal">是否保持原来的路径</param>
/// <param name="isWaterImage"></param>
/// <param name="thumbnails">图片信息</param>
/// <returns></returns>
static public AttachmentInfo UploadImage(HttpPostedFile postedFile, string upLoadForder, bool isSaveOriginal, bool isWaterImage, List<ImageInfo> thumbnails)
{
string strRootFolder = "";
AttachmentInfo oaiInfo = new AttachmentInfo();
//文件名
string strFileName = postedFile.FileName;
//文件扩展名
string strFileExtendName = strFileName.Substring(strFileName.LastIndexOf(".") + 1).ToLower();
//文件真实类型
string strFileType = postedFile.ContentType;
//文件大小
int intFileSize = postedFile.ContentLength;
//文件上传的文件夹目录（绝对路径）
string strFolderMapPath;
if (!upLoadForder.Equals(""))
{
strFolderMapPath = HttpContext.Current.Server.MapPath(upLoadForder);
}
else
{
strFolderMapPath = HttpContext.Current.Server.MapPath("/uploads/" + DateTime.Now.Year + "/" + DateTime.Now.Month + "/");
}
//建立上传目录
if (!Directory.Exists(strFolderMapPath))
{
Directory.CreateDirectory(strFolderMapPath);
}
//取当前时间的字符串
string strNowTimeString = 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();
//文件的新名称(当前日期+文件大小+文件扩展名)
string strNewFileName = strNowTimeString + intFileSize.ToString() + "." + strFileExtendName;
//最终保存文件的路径(文件绝对路径+新生成的文件的新名称)
string strFileMapPath = strFolderMapPath + "/" + strNewFileName;
//返回的文件虚拟目录(相对路径)
string strFileUploadPath = upLoadForder + "/" + strNewFileName;
#region 如果为图片类型
if (strFileType.StartsWith("image") && (strFileExtendName == "bmp" || strFileExtendName == "jpg" || strFileExtendName == "jpeg" || strFileExtendName == "png" || strFileExtendName == "gif"))
{
//是否保存原图
if (isSaveOriginal)
{
//保存原图
postedFile.SaveAs(strFileMapPath);
}
if (thumbnails != null && thumbnails.Count > 0)
{
string strSaveFile = "";
foreach (ImageInfo thumb in thumbnails)
{
if (thumb.Tag != "")
{
strSaveFile = strFolderMapPath + "/" + thumb.Tag + "_" + strNewFileName;
}
else
{
strSaveFile = strFolderMapPath + "/" + strNewFileName;
}
ResizeImage(postedFile.InputStream, strSaveFile, thumb.Width, thumb.Height);
}
}
}
#endregion
else
{
//保存文件
postedFile.SaveAs(strFileMapPath);
}
//HttpContext.Current.Response.Write(strFileUploadPath);
//附件属性
oaiInfo.FileName = strNewFileName;
oaiInfo.FilePath = upLoadForder;
oaiInfo.FileUrl = upLoadForder + strNewFileName;
oaiInfo.FileSize = intFileSize;
return oaiInfo;
}
#endregion
#region 上传图片(原图上传，自定义路径和名称)
/// <summary>
/// 上传图片(原图上传，自定义路径和名称)
/// </summary>
/// <param name="postedFile">上传控件</param>
/// <param name="filePath">存放相对路径</param>
/// <param name="fileName">新文件名</param>
/// <returns></returns>
static public AttachmentInfo UploadImage(HttpPostedFile postedFile, string filePath, string fileName)
{
AttachmentInfo oaiInfo = new AttachmentInfo();
文件名
string strFileName = postedFile.FileName;
//文件扩展名
string strFileExtendName = strFileName.Substring(strFileName.LastIndexOf(".") + 1).ToLower();
//文件真实类型
string strFileType = postedFile.ContentType;
//文件大小
int intFileSize = postedFile.ContentLength;
//文件上传的文件夹目录（绝对路径）
string strFolderMapPath = HttpContext.Current.Server.MapPath(filePath);
//建立上传目录
if (!Directory.Exists(strFolderMapPath))
{
Directory.CreateDirectory(strFolderMapPath);
}
//最终保存文件的路径(文件绝对路径+新生成的文件的新名称)
string strFileMapPath = strFolderMapPath + "/" + fileName;
//返回的文件虚拟目录(相对路径)
string strFileUploadPath = filePath + "/" + fileName;
oaiInfo.ErrorDescription = "";
//保存原图
try
{
postedFile.SaveAs(strFileMapPath);
}
catch (Exception ex)
{
oaiInfo.ErrorDescription = ex.Message;
}
//附件属性
oaiInfo.FileName = fileName;
oaiInfo.FilePath = filePath;
oaiInfo.FileUrl = strFileUploadPath;
oaiInfo.FileSize = intFileSize;
return oaiInfo;
}
#endregion
# region 上传图片(图片byte[]，自定义路径和名称)
/// <summary>
///
/// </summary>
/// <param name="imgbytes">图片byte</param>
/// <param name="filePath">文件夹目录</param>
/// <param name="fileName">文件名</param>
/// <returns></returns>
static public AttachmentInfo UploadImage(byte[] imgbytes, string filePath, string fileName)
{
AttachmentInfo oaiInfo = new AttachmentInfo();
//文件上传的文件夹目录（绝对路径）
string strFolderMapPath = HttpContext.Current.Server.MapPath(filePath);
//建立上传目录
if (!Directory.Exists(strFolderMapPath))
{
Directory.CreateDirectory(strFolderMapPath);
}
//文件大小
int intFileSize = imgbytes.Length;
//最终保存文件的路径(文件绝对路径+新生成的文件的新名称)
string strFileMapPath = strFolderMapPath + "/" + fileName;
//返回的文件虚拟目录(相对路径)
string strFileUploadPath = filePath + "/" + fileName;
oaiInfo.ErrorDescription = "";
using (MemoryStream ms = new MemoryStream(imgbytes))
{
try
{
Bitmap bmp = new Bitmap(ms);
Bitmap bmpnew = new Bitmap(bmp);
bmp.Dispose();
bmp = null;
bmpnew.Save(strFileMapPath, ImageFormat.Jpeg);
bmpnew.Dispose();
}
catch(Exception e)
{
oaiInfo.ErrorDescription = e.Message;
}
}
oaiInfo.FileName = fileName;
oaiInfo.FilePath = strFileMapPath;
oaiInfo.FileUrl = strFileUploadPath;
oaiInfo.FileSize = intFileSize;
return oaiInfo;
}
#endregion
#region 等比缩放图片
public static bool ResizeImage(Stream imageStream, string strSavePath, int width, int height)
{
bool blnRtn = false;
try
{
//创建图片对象
System.Drawing.Image image, resizeimage;
System.Drawing.Image.GetThumbnailImageAbort callb = null;
//获得图片源
image = System.Drawing.Image.FromStream(imageStream);
//计算图片的宽度和高度
double dobWidth = image.Width;
double dobHeight = image.Height;
//重新计算图片等比缩放后的宽度和高度（这里写的比较麻烦，你们看看又没有更好的办法）
if (dobWidth > width || dobHeight > height)
{
if (dobWidth > dobHeight)
{
dobHeight = (int)(dobHeight * (width / dobWidth));
dobWidth = width;
if (dobHeight > height)
{
dobWidth = (int)(dobWidth * (height / dobHeight));
dobHeight = height;
}
}
else
{
dobWidth = (int)(dobWidth * (height / dobHeight));
dobHeight = height;
if (dobWidth > width)
{
dobHeight = (int)(dobHeight * (width / dobWidth));
dobWidth = width;
}
}
}
else
{
}
//缩放后图片
resizeimage = image.GetThumbnailImage((int)dobWidth, (int)dobHeight, callb, new System.IntPtr());
//保存图片
resizeimage.Save(strSavePath);
//释放resizeimage对象的资源
image.Dispose();
//释放resizeimage对象的资源
resizeimage.Dispose();
blnRtn = true;
//imageStream.Close();
//imageStream.Dispose();
}
catch (Exception ex)
{
throw new Exception("ex:" + ex.Message);
blnRtn = false;
}
return blnRtn;
}
#endregion
#region 给图片加上水印
public static bool WaterImage(Stream imageStream, string strSavePath)
{
bool blnRtn = false;
try
{
//获得图片源和水印图片源
System.Drawing.Image image = System.Drawing.Image.FromStream(imageStream);
System.Drawing.Image imageWater = System.Drawing.Image.FromFile(HttpContext.Current.Server.MapPath("/watermark.png"));
//根据图片源创建BitMap
Bitmap bitmap = new Bitmap(image, image.Width, image.Height);
Graphics g = Graphics.FromImage(bitmap);
//计算画框的宽度高度以及位置
float rectWidth = imageWater.Width;
float rectHeight = imageWater.Height;
float rectX = image.Width - imageWater.Width;
float rectY = image.Height - imageWater.Height;
//加上水印
g.DrawImage(imageWater, rectX, rectY, rectWidth, rectHeight);
//释放对象
image.Dispose();
imageWater.Dispose();
//保存图片
bitmap.Save(strSavePath, ImageFormat.Jpeg);
//释放对象
g.Dispose();
bitmap.Dispose();
}
catch
{
blnRtn = false;
}
return blnRtn;
}
#endregion
#region 产生图片验证码
/// <summary>
/// 产生图片验证码
/// </summary>
/// <param name="checkCode"></param>
public static void CreateCheckImage(string checkCode)
{
if ((checkCode != null) && !(checkCode.Trim() == string.Empty))
{
Bitmap image = new Bitmap((int)Math.Ceiling((double)(checkCode.Length * 12.5)), 0x16);
Graphics graphics = Graphics.FromImage(image);
try
{
int num;
Random random = new Random();
graphics.Clear(Color.White);
for (num = 0; num < 0x19; num++)
{
int num2 = random.Next(image.Width);
int num3 = random.Next(image.Width);
int num4 = random.Next(image.Height);
int num5 = random.Next(image.Height);
graphics.DrawLine(new Pen(Color.Silver), num2, num4, num3, num5);
}
Font font = new Font("Arial", 12f, FontStyle.Italic | FontStyle.Bold);
LinearGradientBrush brush = new LinearGradientBrush(new Rectangle(0, 0, image.Width, image.Height), Color.Blue, Color.DarkRed, 1.2f, true);
graphics.DrawString(checkCode, font, brush, (float)2f, (float)2f);
for (num = 0; num < 100; num++)
{
int x = random.Next(image.Width);
int y = random.Next(image.Height);
image.SetPixel(x, y, Color.FromArgb(random.Next()));
}
graphics.DrawRectangle(new Pen(Color.Silver), 0, 0, image.Width - 1, image.Height - 1);
MemoryStream stream = new MemoryStream();
image.Save(stream, ImageFormat.Gif);
HttpContext.Current.Response.ClearContent();
HttpContext.Current.Response.ContentType = "image/Gif";
HttpContext.Current.Response.BinaryWrite(stream.ToArray());
}
finally
{
graphics.Dispose();
image.Dispose();
}
}
}
public byte[] CreateImage(string checkCode)
{
if (checkCode == null || checkCode.Trim() == string.Empty) return null;
//生成BitMap图像
Bitmap image = new Bitmap((int)Math.Ceiling((double)(checkCode.Length * 12.5)), 0x16);
Graphics graphics = Graphics.FromImage(image);
try
{
int num;
Random random = new Random();
graphics.Clear(Color.White);
for (num = 0; num < 0x19; num++)
{
int num2 = random.Next(image.Width);
int num3 = random.Next(image.Width);
int num4 = random.Next(image.Height);
int num5 = random.Next(image.Height);
graphics.DrawLine(new Pen(Color.Silver), num2, num4, num3, num5);
}
Font font = new Font("Arial", 12f, FontStyle.Italic | FontStyle.Bold);
LinearGradientBrush brush = new LinearGradientBrush(new Rectangle(0, 0, image.Width, image.Height), Color.Blue, Color.DarkRed, 1.2f, true);
graphics.DrawString(checkCode, font, brush, (float)2f, (float)2f);
for (num = 0; num < 100; num++)
{
int x = random.Next(image.Width);
int y = random.Next(image.Height);
image.SetPixel(x, y, Color.FromArgb(random.Next()));
}
//画图片的边框线
graphics.DrawRectangle(new Pen(Color.Silver), 0, 0, image.Width - 1, image.Height - 1);
System.IO.MemoryStream ms = new System.IO.MemoryStream();
//将图像保存到指定流
image.Save(ms, System.Drawing.Imaging.ImageFormat.Gif);
return ms.ToArray();
}
finally
{
graphics.Dispose();
image.Dispose();
}
}
#endregion
/// <summary>
/// 根据地址图片宽和高
/// </summary>
/// <param name="strImageUrl"></param>
/// <returns></returns>
public static ImageInfo GetImageSize(string strImageUrl)
{
ImageInfo imageInfo = new ImageInfo();
strImageUrl = HttpContext.Current.Server.MapPath(strImageUrl);
if (File.Exists(strImageUrl))
{
Image imageOb = Image.FromFile(strImageUrl);
imageInfo.Width = imageOb.Width;
imageInfo.Height = imageOb.Height;
}
return imageInfo;
}
/// <summary>
/// 根据地址图片高度
/// </summary>
/// <param name="strImageUrl"></param>
/// <returns></returns>
public static int GetImageHeight(string strImageUrl)
{
return GetImageSize(strImageUrl).Height;
}
// 影音快传图片地址
// 手机端域名为m.user.xxxx.cc，电脑端域名为my.xxxx.cc
// 导致影音快传页面调用时缺省域名图片不显示，所以在上传时直接以绝对地址形式上传
public static string setImgUrl(string strImgUrl)
{
if (strImgUrl.Contains("http") && strImgUrl.Contains("xxxx"))
{
return strImgUrl;
}
if (!strImgUrl.Contains("http") && strImgUrl.Contains("xxxx"))
{
return "http://" + strImgUrl;
}
if (!strImgUrl.Contains("http") && !strImgUrl.Contains("xxxx"))
{
return "http://user.m.xxxx.cc" + strImgUrl;
}
return strImgUrl;
}
public static bool SaveImage(Stream imageStream, string strSavePath)
{
bool blnRtn = false;
try
{
//创建图片对象
System.Drawing.Image image, resizeimage;
System.Drawing.Image.GetThumbnailImageAbort callb = null;
//获得图片源
image = System.Drawing.Image.FromStream(imageStream);
image.Save(strSavePath);
//释放resizeimage对象的资源
image.Dispose();
blnRtn = true;
//imageStream.Close();
//imageStream.Dispose();
}
catch (Exception ex)
{
//throw new Exception("ex:" + ex.Message);
blnRtn = false;
}
return blnRtn;
}
#region 图片无损压缩
/// <summary>
/// 无损压缩图片
/// </summary>
/// <param name="sFile">原图片地址</param>
/// <param name="dFile">压缩后保存图片地址</param>
/// <param name="flag">压缩质量（数字越小压缩率越高）1-100</param>
/// <param name="size">压缩后图片的最大大小</param>
/// <param name="sfsc">是否是第一次调用</param>
/// <returns></returns>
public static bool CompressImage(string sFile, string dFile, int flag = 90, int size = 300, bool sfsc = true)
{
try
{
//如果是第一次调用，原始图像的大小小于要压缩的大小，则直接复制文件，并且返回true
FileInfo firstFileInfo = new FileInfo(sFile);
if (sfsc == true && firstFileInfo.Length < size * 1024)
{
firstFileInfo.CopyTo(dFile, true);
return true;
}
Image iSource = Image.FromFile(sFile);
ImageFormat tFormat = iSource.RawFormat;
int dHeight = iSource.Height / 2;
int dWidth = iSource.Width / 2;
int sW = 0, sH = 0;
//按比例缩放
Size tem_size = new Size(iSource.Width, iSource.Height);
if (tem_size.Width > dHeight || tem_size.Width > dWidth)
{
if ((tem_size.Width * dHeight) > (tem_size.Width * dWidth))
{
sW = dWidth;
sH = (dWidth * tem_size.Height) / tem_size.Width;
}
else
{
sH = dHeight;
sW = (tem_size.Width * dHeight) / tem_size.Height;
}
}
else
{
sW = tem_size.Width;
sH = tem_size.Height;
}
Bitmap ob = new Bitmap(dWidth, dHeight);
Graphics g = Graphics.FromImage(ob);
g.Clear(Color.WhiteSmoke);
g.CompositingQuality = System.Drawing.Drawing2D.CompositingQuality.HighQuality;
g.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality;
g.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.HighQualityBicubic;
g.DrawImage(iSource, new Rectangle((dWidth - sW) / 2, (dHeight - sH) / 2, sW, sH), 0, 0, iSource.Width, iSource.Height, GraphicsUnit.Pixel);
g.Dispose();
//以下代码为保存图片时，设置压缩质量
EncoderParameters ep = new EncoderParameters();
long[] qy = new long[1];
qy[0] = flag;//设置压缩的比例1-100
EncoderParameter eParam = new EncoderParameter(System.Drawing.Imaging.Encoder.Quality, qy);
ep.Param[0] = eParam;
try
{
ImageCodecInfo[] arrayICI = ImageCodecInfo.GetImageEncoders();
ImageCodecInfo jpegICIinfo = null;
for (int x = 0; x < arrayICI.Length; x++)
{
if (arrayICI[x].FormatDescription.Equals("JPEG"))
{
jpegICIinfo = arrayICI[x];
break;
}
}
if (jpegICIinfo != null)
{
ob.Save(dFile, jpegICIinfo, ep);//dFile是压缩后的新路径
FileInfo fi = new FileInfo(dFile);
if (fi.Length > 1024 * size)
{
flag = flag - 10;
CompressImage(sFile, dFile, flag, size, false);
}
}
else
{
ob.Save(dFile, tFormat);
}
return true;
}
catch
{
return false;
}
finally
{
iSource.Dispose();
ob.Dispose();
}
}
catch
{
return false;
}
}
#endregion
}
