使用FileUpload控件上传图片并自动生成缩略图、带文字和图片的水印图

最新推荐文章于 2022-10-08 12:19:58 发布

zwei1121

最新推荐文章于 2022-10-08 12:19:58 发布

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文章标签： string path 服务器 button image server

使用FileUpload控件上传图片并自动生成缩略图、带文字和图片的水印图

<%@ Page Language="C#" AutoEventWireup="true" CodeFile="upfile.aspx.cs" Inherits="upfile_upfile" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

using System;
using System.Data;
using System.Configuration;
using System.Collections;
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;

public partial class upfile_upfile : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{ }

protected void Button1_Click(object sender, EventArgs e)
{
    if (FileUpload1.HasFile)
    {
        string fileContentType = FileUpload1.PostedFile.ContentType;
        if (fileContentType == "image/bmp" || fileContentType == "image/gif" || fileContentType == "image/pjpeg")
        {
          string name = FileUpload1.PostedFile.FileName;             // 客户端文件路径

          FileInfo file = new FileInfo(name);
          string fileName = file.Name;                         // 文件名称
          string fileName_s = "s_" + file.Name;                   // 缩略图文件名称
          string fileName_sy = "sy_" + file.Name;                 // 水印图文件名称（文字）
          string fileName_syp = "syp_" + file.Name;               // 水印图文件名称（图片）
          string webFilePath = Server.MapPath("file/" + fileName);     // 服务器端文件路径
          string webFilePath_s = Server.MapPath("file/" + fileName_s);　　// 服务器端缩略图路径
          string webFilePath_sy = Server.MapPath("file/" + fileName_sy);　// 服务器端带水印图路径(文字)
          string webFilePath_syp = Server.MapPath("file/" + fileName_syp);　// 服务器端带水印图路径(图片)
          string webFilePath_sypf = Server.MapPath("file/shuiyin.jpg");　// 服务器端水印图路径(图片)

          if (!File.Exists(webFilePath))
          {
            try
            {
                FileUpload1.SaveAs(webFilePath);                     // 使用 SaveAs 方法保存文件
                AddShuiYinWord(webFilePath, webFilePath_sy);
                AddShuiYinPic(webFilePath, webFilePath_syp, webFilePath_sypf);
                MakeThumbnail(webFilePath, webFilePath_s, 130, 130, "Cut");   // 生成缩略图方法
                Label1.Text = "提示：文件“" + fileName + "”成功上传，并生成“" + fileName_s + "”缩略图，文件类型为：" +

FileUpload1.PostedFile.ContentType + "，文件大小为：" + FileUpload1.PostedFile.ContentLength + "B";
            }
            catch (Exception ex)
            {
                Label1.Text = "提示：文件上传失败，失败原因：" + ex.Message;
            }
          }
          else
          {
            Label1.Text = "提示：文件已经存在，请重命名后上传";
          }
        }
        else
        {
          Label1.Text = "提示：文件类型不符";
        }
    }
}
/**//// <summary>
/// 生成缩略图
/// </summary>
/// <param name="originalImagePath">源图路径（物理路径）</param>
/// <param name="thumbnailPath">缩略图路径（物理路径）</param>
/// <param name="width">缩略图宽度</param>
/// <param name="height">缩略图高度</param>
/// <param name="mode">生成缩略图的方式</param>
public static void MakeThumbnail(string originalImagePath, string thumbnailPath, int width, int height, string mode)
{
    System.Drawing.Image originalImage = System.Drawing.Image.FromFile(originalImagePath);

int towidth = width;
int toheight = height;

    int x = 0;
    int y = 0;
    int ow = originalImage.Width;
    int oh = originalImage.Height;

    switch (mode)
    {
        case "HW"://指定高宽缩放（可能变形）
          break;
        case "W"://指定宽，高按比例
          toheight = originalImage.Height * width / originalImage.Width;
          break;
        case "H"://指定高，宽按比例
          towidth = originalImage.Width * height / originalImage.Height;
          break;
        case "Cut"://指定高宽裁减（不变形）
          if ((double)originalImage.Width / (double)originalImage.Height > (double)towidth / (double)toheight)
          {
            oh = originalImage.Height;
            ow = originalImage.Height * towidth / toheight;
            y = 0;
            x = (originalImage.Width - ow) / 2;
          }
          else
          {
            ow = originalImage.Width;
            oh = originalImage.Width * height / towidth;
            x = 0;
            y = (originalImage.Height - oh) / 2;
          }
          break;
        default:
          break;
    }

//新建一个bmp图片
System.Drawing.Image bitmap = new System.Drawing.Bitmap(towidth, toheight);

//新建一个画板
System.Drawing.Graphics g = System.Drawing.Graphics.FromImage(bitmap);

//设置高质量插值法
g.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.High;

//设置高质量,低速度呈现平滑程度
g.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality;

//清空画布并以透明背景色填充
g.Clear(System.Drawing.Color.Transparent);

    //在指定位置并且按指定大小绘制原图片的指定部分
    g.DrawImage(originalImage, new System.Drawing.Rectangle(0, 0, towidth, toheight),
        new System.Drawing.Rectangle(x, y, ow, oh),
        System.Drawing.GraphicsUnit.Pixel);

    try
    {
        //以jpg格式保存缩略图
        bitmap.Save(thumbnailPath, System.Drawing.Imaging.ImageFormat.Jpeg);
    }
    catch (System.Exception e)
    {
        throw e;
    }
    finally
    {
        originalImage.Dispose();
        bitmap.Dispose();
        g.Dispose();
    }
}

/**//// <summary>
/// 在图片上增加文字水印
/// </summary>
/// <param name="Path">原服务器图片路径</param>
/// <param name="Path_sy">生成的带文字水印的图片路径</param>
protected void AddShuiYinWord(string Path, string Path_sy)
{
    string addText = "测试水印";
    System.Drawing.Image image = System.Drawing.Image.FromFile(Path);
    System.Drawing.Graphics g = System.Drawing.Graphics.FromImage(image);
    g.DrawImage(image, 0, 0, image.Width, image.Height);
    System.Drawing.Font f = new System.Drawing.Font("Verdana", 16);
    System.Drawing.Brush b = new System.Drawing.SolidBrush(System.Drawing.Color.Blue);

g.DrawString(addText, f, b, 15, 15);
g.Dispose();

image.Save(Path_sy);
image.Dispose();
}

/**//// <summary>
/// 在图片上生成图片水印
/// </summary>
/// <param name="Path">原服务器图片路径</param>
/// <param name="Path_syp">生成的带图片水印的图片路径</param>
/// <param name="Path_sypf">水印图片路径</param>
protected void AddShuiYinPic(string Path, string Path_syp, string Path_sypf)
{
    System.Drawing.Image image = System.Drawing.Image.FromFile(Path);
    System.Drawing.Image copyImage = System.Drawing.Image.FromFile(Path_sypf);
    System.Drawing.Graphics g = System.Drawing.Graphics.FromImage(image);
    g.DrawImage(copyImage, new System.Drawing.Rectangle(image.Width - copyImage.Width, image.Height - copyImage.Height,

copyImage.Width, copyImage.Height), 0, 0, copyImage.Width,copyImage.Height, System.Drawing.GraphicsUnit.Pixel);
g.Dispose();

image.Save(Path_syp);
image.Dispose();
}
}