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$req=POST 'https://www.abc.com/fileUpload.aspx', Content_Type=>'multip +art/form_data', Content => [__VIEWSTATE=>'dDwtMjRrKEnBI=', aa=>'I', ... $req->as_string;
POST https://www.abcd.com/fileUpload.aspx Content-Length: 411 Content-Type: multipart/form_data VIEWSTATE=dDwtMjRrKEnBI%3D&aa=I&file1=ABCD.DAT