【优化】C#图片水印和缩略图片

前段时间写的在实际运用中,发现了很多不足之处,所以优化了一下,当然还是有问题的（不过基本使用没什么问题）:

考虑到有些图片是放置在本站内,增加了一个临时文件处理方式FileCache(Delete,Save),对于节省空间来说还是可以用的

//使用方式及参数

A、缩略图片

View Code

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

using System.Web;
using System.IO;
using System.Drawing;

namespace ImgClassLib
{
/// <summary>
/// 图片处理:水印图片
/// </summary>
public class watermark
{
/// <summary>
/// 水印图片
/// 【如果图片需要缩略,请使用skeletonize.Resizepic()方法对图片进行缩略】
/// 返回图片虚拟路径,和一个警告信息,可根据此信息获取图片合成信息
/// </summary>
/// <param name="picpath">需要水印的图片路径</param>
/// <param name="waterspath">水印图片路径</param>
/// <param name="watermodel">水印模式</param>
/// <param name="spath">文件保存路径</param>
/// <param name="imgtype">保存文件类型</param>
/// <param name="filecache">原文件处理方式</param>
/// <param name="warning">处理警告信息</param>
/// <returns>错误,返回错误信息;成功,返回图片路径</returns>

public static string makewatermark(string picpath, string waterspath, commonfun.WaterType watermodel, string spath, commonfun.ImageType imgtype, commonfun.FileCache filecache, out string warning)
{
#region
//反馈信息
System.Text.StringBuilder checkmessage = new System.Text.StringBuilder();

//检测源文件
string _sourceimg_common_mappath = "";
bool checkfile = false;

//检测水印源文件
string _sourceimg_water_mappath = "";
bool checkfilewater = false;

checkfile = commonfun.FileExistMapPath(picpath,commonfun.FileCheckModel.C, out _sourceimg_common_mappath);
checkfilewater = commonfun.FileExistMapPath(waterspath, commonfun.FileCheckModel.C, out _sourceimg_water_mappath);

System.Drawing.Image _sourceimg_common = null;
System.Drawing.Image _sourceimg_water = null;

if (checkfile == true)
{
//从指定源文件,创建image对象
_sourceimg_common = System.Drawing.Image.FromFile(_sourceimg_common_mappath);
}
else
{
checkmessage.Append("error:找不到需要的水印图片!" + picpath + ";");
}
if (checkfilewater == true)
{
//从指定源文件,创建image对象
_sourceimg_water = System.Drawing.Image.FromFile(_sourceimg_water_mappath);
}
else
{
checkmessage.Append("error:找不到需要水印图片!" + waterspath + ";");
}
#endregion

#region
if (string.IsNullOrEmpty(checkmessage.ToString()))
{
//源图宽、高
int _sourceimg_common_width =_sourceimg_common.Width;
int _sourceimg_common_height = _sourceimg_common.Height;

//水印图片宽、高
int _sourceimg_water_width = _sourceimg_water.Width;
int _sourceimg_water_height =_sourceimg_water.Height;

#region 水印坐标
//水印坐标
int _sourceimg_water_point_x = 0;
int _sourceimg_water_point_y = 0;

switch (watermodel)
{
case commonfun.WaterType.Center:
_sourceimg_water_point_x = (_sourceimg_common_width - _sourceimg_water_width) / 2;
_sourceimg_water_point_y = (_sourceimg_common_height - _sourceimg_water_height) / 2;
; break;
case commonfun.WaterType.CenterDown:
_sourceimg_water_point_x = (_sourceimg_common_width - _sourceimg_water_width) / 2;
_sourceimg_water_point_y = _sourceimg_common_height - _sourceimg_water_height;
; break;
case commonfun.WaterType.CenterUp:
_sourceimg_water_point_x = (_sourceimg_common_width - _sourceimg_water_width) / 2;
_sourceimg_water_point_y = 0;
; break;
case commonfun.WaterType.LeftDown:
_sourceimg_water_point_x = 0;
_sourceimg_water_point_y = _sourceimg_common_height - _sourceimg_water_height;
; break;
case commonfun.WaterType.LeftUp:
; break;
case commonfun.WaterType.Random:
Random r = new Random();
int x_random = r.Next(0, _sourceimg_common_width);
int y_random = r.Next(0, _sourceimg_common_height);

_sourceimg_water_point_x = x_random > (_sourceimg_common_width - _sourceimg_water_width)
? _sourceimg_common_width - _sourceimg_water_width : x_random;

_sourceimg_water_point_y = y_random > (_sourceimg_common_height - _sourceimg_water_height)
? _sourceimg_common_height - _sourceimg_water_height : y_random;

; break;
case commonfun.WaterType.RightDown:
_sourceimg_water_point_x = _sourceimg_common_width - _sourceimg_water_width;
_sourceimg_water_point_y = _sourceimg_common_height - _sourceimg_water_height;
; break;
case commonfun.WaterType.RightUp:
_sourceimg_water_point_x = _sourceimg_common_width - _sourceimg_water_width;
_sourceimg_water_point_y = 0;
; break;
}
#endregion

//从源图创建画板
System.Drawing.Graphics _g_common = Graphics.FromImage(_sourceimg_common);

//设置画笔
_g_common.CompositingMode = System.Drawing.Drawing2D.CompositingMode.SourceOver;
_g_common.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.HighQualityBicubic;
_g_common.PixelOffsetMode = System.Drawing.Drawing2D.PixelOffsetMode.Half;

//绘制水印图片
_g_common.DrawImage(_sourceimg_water, new Rectangle(_sourceimg_water_point_x, _sourceimg_water_point_y, _sourceimg_water_width, _sourceimg_water_height), new Rectangle(0, 0, _sourceimg_water_width, _sourceimg_water_height), GraphicsUnit.Pixel);

//保存图片
string _spath_common_mappath = "";
//全局文件名

//获取图片类型的hashcode值,生成图片后缀名
int extro = imgtype.GetHashCode();
string extend = extro == 0 ? ".jpg" : (extro == 1 ? ".gif" : (extro == 2 ? ".png" : ".jpg"));

spath = spath + Guid.NewGuid().ToString() + extend;

commonfun.FileExistMapPath(spath,commonfun.FileCheckModel.M, out _spath_common_mappath);

switch (imgtype)
{
case commonfun.ImageType.JPEG: _sourceimg_common.Save(_spath_common_mappath, System.Drawing.Imaging.ImageFormat.Jpeg); break;
case commonfun.ImageType.GIF: _sourceimg_common.Save(_spath_common_mappath, System.Drawing.Imaging.ImageFormat.Gif); break;
case commonfun.ImageType.PNG: _sourceimg_common.Save(_spath_common_mappath, System.Drawing.Imaging.ImageFormat.Png); break;
}

//释放
_sourceimg_common.Dispose();
_sourceimg_water.Dispose();
_g_common.Dispose();

//处理原文件
int filecachecode = filecache.GetHashCode();
//删除原文件
if (filecachecode == 1)
{
System.IO.File.Delete(_sourceimg_common_mappath);
}

warning = "";
return spath;

}
#endregion

//释放
if (_sourceimg_common != null)
{
_sourceimg_common.Dispose();
}
if (_sourceimg_water!=null)
{
_sourceimg_water.Dispose();
}

warning = checkmessage.ToString().TrimEnd(';');
return "";
}
}
}