[VB.NET]求救线程下载程序

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求救线程下载程序
求救线程下载程序,我现在采用的是
Try

Dim sHttpWebClinet As System.Net.WebClient = New System.Net.WebClient
Dim myDatabuffer As Byte() = sHttpWebClinet.DownloadData(File_Path) ''将网页上的内容下载到byte类型的数组，网址File_Path，myDatabuffer存储下载的源文件
Dim File_Con As String = System.Text.Encoding.GetEncoding( "GB2312 ").GetString(myDatabuffer) ''将下载的内容放进一个字符串File_Con，剩下的就是对这个字符串取值了
sHttpWebClinet.Dispose() ''释放空间
sHttpWebClinet = Nothing ''清空
Return File_Con ''返回源文件File_Con
Catch ex As Exception
Return " "
End Try

速度很慢,想用vb.net启动线程,本人对线程完全不懂
请高手或者做个用vb.net线程下载的朋友告诉我点代码,具体一点
谢谢各位了
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线程!=提速
如果是分段下载，不能用WebClient。
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