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上傳圖片並生成略縮圖(c#)

編輯：關於C語言

參數說明
FileBox:上傳表單中的表單名
SavePath:保存路徑
ThumbnailWidth:略縮圖寬
ThumbnailHeight:略縮圖高
FilePath:文件保存路徑（輸出參數）
FileName:文件名稱（輸出參數）
LastError:（輸出錯誤）
public static bool UploadImages(System.Web.UI.HtmlControls.HtmlInputFile FileBox,string SavePath,Int32 ThumbnailWidth,Int32 ThumbnailHeight,out String FilePath,out String FileName,out string LastError)
{
DateTime datTime=System.DateTime.Now;
String strTemp;
string strFileName = FileBox.PostedFile.FileName;
bool blnResult;
LastError="";
System.Drawing.Image xImage;
System.Drawing.Bitmap xBitmap;
int PhotoHeight,PhotoWidth;
string BasePath=System.Web.HttpContext.Current.Server.MapPath("../");
Rectangle NewPhoto;
System.Drawing.Imaging.ImageFormat xObject;
string Extension="";
FileName="";
FilePath="";

try
{
if(strFileName=="")
{
LastError="請點擊浏覽選擇要上傳的文件!";
return false;
}
if(Convert.ToDecimal(FileBox.PostedFile.ContentLength)<= 2000000 &&Convert.ToDecimal(FileBox.PostedFile.ContentLength)>1500)
{
//查看擴展名是否合法
Extension=Path.GetExtension(strFileName);
Extension=Extension.ToLower();
if(Extension==".gif" || Extension==".jpg" || Extension==".jpeg" || Extension==".bmp")
{
switch(Extension)
{
case ".gif":
xObject=System.Drawing.Imaging.ImageFormat.Gif;
break;
case ".bmp":
xObject=System.Drawing.Imaging.ImageFormat.Bmp;
break;
default:
xObject=System.Drawing.Imaging.ImageFormat.Jpeg;

break;
}
}
else
{
LastError="上傳的文件不是有效的圖片文件，請上傳格式為：.gif.jpg.bmp的文件！";
return false;
}
//-----------------------------
//生成保存的文件路徑及文件名
//-----------------------------
strTemp = datTime.ToShortDateString().Replace( "-", "");
FileName = datTime.ToLongTimeString().Replace(":","")+ Extension;
FilePath = SavePath + strTemp + "/";
FrIEndlib.Function.CreateDirectory(BasePath + FilePath);
//保存大圖
xImage=System.Drawing.Bitmap.FromStream(FileBox.PostedFile.InputStream);

xImage.Save(BasePath+FilePath+FileName);
xImage.Dispose();
//-----------------------------
//開始生成縮略圖
//-----------------------------
xBitmap=new Bitmap(BasePath+FilePath+FileName);//------------------

PhotoHeight=xBitmap.Height;
PhotoWidth=xBitmap.Width;
// //判斷圖片的形狀
if(Convert.ToDecimal(PhotoHeight)/Convert.ToDecimal(PhotoWidth)>Convert.ToDecimal(ThumbnailHeight)/Convert.ToDecimal(ThumbnailWidth))//高有余
{
PhotoHeight=Convert.ToInt16((Convert.ToDecimal(ThumbnailHeight)/Convert.ToDecimal(ThumbnailWidth))*Convert.ToDecimal(PhotoWidth));
NewPhoto=new Rectangle(0,0,PhotoWidth,PhotoHeight);
}
else if(Convert.ToDecimal(PhotoHeight)/Convert.ToDecimal(PhotoWidth)<Convert.ToDecimal(ThumbnailHeight)/Convert.ToDecimal(ThumbnailWidth))
{
PhotoWidth=Convert.ToInt16((Convert.ToDecimal(ThumbnailWidth)/Convert.ToDecimal(ThumbnailHeight))*Convert.ToDecimal(PhotoHeight));
NewPhoto=new
Rectangle(Convert.ToInt16((Convert.ToDecimal(xBitmap.Width)-Convert.ToDecimal(PhotoWidth))/2),0,PhotoWidth,PhotoHeight);
}
else
{
NewPhoto= newRectangle(0,0,PhotoWidth,PhotoHeight); < BR> }
System.Drawing.Image myBitmap;
myBitmap=xBitmap.Clone(NewPhoto,System.Drawing.Imaging.PixelFormat.DontCare);
System.Drawing.Image.GetThumbnailImageAbort myCallback = new
System.Drawing.Image.GetThumbnailImageAbort(ThumbnailCallback);
System.Drawing.Image myThumbnail =
myBitmap.GetThumbnailImage(ThumbnailWidth,ThumbnailHeight, myCallback,
IntPtr.Zero); myThumbnail.Save(BasePath + FilePath +"s"+FileName,xObject);
myThumbnail.Dispose(); myBitmap.Dispose(); xBitmap.Dispose(); return true; }
else
{
blnResult=false; LastError="不能上傳大於2M及小於1.5K的圖片!";
}
}< BR> catch (Exception ex) {
throw new System.Exception((ex.Message + ("\r\n" + ex.StackTrace)));
}
return blnResult;
}
private static bool ThumbnailCallback() { return false; }

關於C語言