image.aspx文件
<%@ Page Language="C#" AutoEventWireup="true" CodeFile="image.aspx.cs" Inherits="image" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>無標題頁</title>
</head>
<body>
<form id="form1" runat="server">
<div>
<asp:FileUpload ID="UploadFile" runat="server" />
<asp:Button ID="btnUploadPicture" runat="server" OnClick="btnUploadPicture_Click"
Text="上傳" /></div>
</form>
</body>
</html>
image.aspx.cs文件
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.Drawing;
public partial class image : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
}
protected void btnUploadPicture_Click(object sender, EventArgs e)
{
//Response.Write(this.UploadFile.PostedFile.ContentType.ToString());
//檢查上傳文件的格式是否有效
if (this.UploadFile.PostedFile.ContentType.ToLower().IndexOf("image") < 0)
{
Response.Write("上傳圖片格式無效！");
return;
}
//生成原圖
Byte[] oFileByte = new byte[this.UploadFile.PostedFile.ContentLength];
System.IO.Stream oStream = this.UploadFile.PostedFile.InputStream;
System.Drawing.Image oImage = System.Drawing.Image.FromStream(oStream);
int oWidth = oImage.Width; //原圖寬度
int oHeight = oImage.Height; //原圖高度
int tWidth = 100; //設置縮略圖初始寬度
int tHeight = 100; //設置縮略圖初始高度
//按比例計算出縮略圖的寬度和高度
if (oWidth >= oHeight)
{
tHeight = (int)Math.Floor(Convert.ToDouble(oHeight) * (Convert.ToDouble(tWidth) / Convert.ToDouble(oWidth)));
}
else
{
tWidth = (int)Math.Floor(Convert.ToDouble(oWidth) * (Convert.ToDouble(tHeight) / Convert.ToDouble(oHeight)));
}
//生成縮略原圖
Bitmap tImage = new Bitmap(tWidth, tHeight);
Graphics g = Graphics.FromImage(tImage);
g.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.High; //設置高質量插值法
g.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality;//設置高質量,低速度呈現平滑程度
g.Clear(Color.Transparent); //清空畫布並以透明背景色填充
g.DrawImage(oImage, new Rectangle(0, 0, tWidth, tHeight), new Rectangle(0, 0, oWidth, oHeight), GraphicsUnit.Pixel);
string oFullName = Server.MapPath(".") + "/" + "o" + DateTime.Now.ToShortDateString().Replace("-", "") + DateTime.Now.Hour.ToString() + DateTime.Now.Minute.ToString() + DateTime.Now.Second.ToString() + DateTime.Now.Millisecond.ToString() + ".jpg"; //保存原圖的物理路徑
string tFullName = Server.MapPath(".") + "/" + "t" + DateTime.Now.ToShortDateString().Replace("-", "") + DateTime.Now.Hour.ToString() + DateTime.Now.Minute.ToString() + DateTime.Now.Second.ToString() + DateTime.Now.Millisecond.ToString() + ".jpg"; //保存縮略圖的物理路徑
try
{
//以JPG格式保存圖片
oImage.Save(oFullName, System.Drawing.Imaging.ImageFormat.Jpeg);
tImage.Save(tFullName, System.Drawing.Imaging.ImageFormat.Jpeg);
}
catch (Exception ex)
{
throw ex;
}
finally
{
//釋放資源
oImage.Dispose();
g.Dispose();
tImage.Dispose();
}
}
}