各位:我们公司有个图片库,是存在硬盘上的.现在网站显示的预览图片都是提取图片的路径,图片路径是存在数据库中的,然后显示,但是图片库中的图片都很大(2-3MB).所以预览页面显示很慢.我想让预览页面显示快一点,我的初步解决方法是,图片上传的时候生成两个图,一个是预览图,一个是原图,分别放在两个文件夹下,把路径存入数据库的不同字段,在预览页面查看的时候,提取预览图,在查看详细信息的时候提取原图.不知道大家还有没有其他好的解决方法.谢谢各位同行!
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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.HtmlControls;
using System.Drawing;
using System.Drawing.Imaging;
using System.IO;
/// <summary>
/// MakePic 的摘要说明
/// </summary>
public class MakePic
{
public MakePic()
{
//
// TODO: 在此处添加构造函数逻辑
//
}
public 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
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(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 Rectangle(0, 0, towidth, toheight),
new Rectangle(x, y, ow, oh),
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();
}
}//按比例生成高质量缩略图
}
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