本人新手，最近在测试post，下面是测试成功的语句，只需要修改传入内容和webservice地址就行了

Dim xmlRequest As String = e.Form.Controls("TextBox2").text     ----post传入的内容
Dim xml As String = xmlRequest  \'实例化一个字符转码对象\'
Dim encoding As System.Text.Encoding = System.Text.Encoding.GetEncoding("utf-8")
\'创建一个web请求对象\'
Dim request As System.Net.WebRequest = System.Net.WebRequest.Create("http://192.168.1.18:5566/services/RouteService?wsdl")      ----webservice地址
\'设置请求方式为post\'
request.Method = "POST"
\'定义字节数组\'
Dim postdata() As System.Byte = encoding.GetBytes(xmlRequest)
\'设置request对象的请求字节的长度\'
request.ContentLength = postdata.Length
\'获取request对象的数据流\'
Dim requesstream As System.IO.Stream = request.GetRequestStream()
\'将数据内容填充到流中\'
requesstream.Write(postdata, 0, postdata.Length)
\'关闭流\'
requesstream.Close()
\'根据请求的request对象获取响应的response对象\'
Dim response As System.Net.WebResponse = request.GetResponse()
\'获取response数据流对象\'
Dim responsestream As New System.IO.StreamReader(response.GetResponseStream())
\'将response流中的数据读取\'
Dim html As String = responsestream.ReadToEnd()
requesstream.Close()
response.Close()
\'返回本次请求的响应数据\'
e.Form.Controls("TextBox3").text=html       ----post传出内容