本文实例讲述了C#判断一个图像是否是透明的GIF图的方法。分享给大家供大家参考。具体如下：
1. 使用方法如下：
System.Drawing.Image objImage = DownloadImage("https://www.google.com/images/srpr/logo3w.png");
if (IsTransparentPalette(objImage.Palette)) {//your code....}
2. C#代码如下：
public bool IsTransparentPalette(System.Drawing.Imaging.ColorPalette palette)
{
if (palette.Flags!= 1 )
return false;
int total_colors = palette.Entries.GetLength(0);
for (int i = 0; i < total_colors - 1; i++)
{
if (palette.Entries[i].A != 0)
{
return false;
}
}
return true;
}
public System.Drawing.Image DownloadImage(string url)
{
System.Drawing.Image tmpImage = null;
try
{
HttpWebRequest request = (HttpWebRequest)WebRequest.Create(url);
request.AllowWriteStreamBuffering = true;
request.UserAgent = UserAgent;
request.Accept = "GET HTTP/1.1";
request.Timeout = 2000;
System.Net.WebResponse webResponse = request.GetResponse();
System.IO.Stream webStream = webResponse.GetResponseStream();
if (webStream != null) tmpImage = System.Drawing.Image.FromStream(webStream);
webResponse.Close();
webResponse.Close();
}
catch (Exception exception)
{
return null;
}
return tmpImage;
}
希望本文所述对大家的C#程序设计有所帮助。
