string postData="TextBox1="+this.textBox1.Text+"&TextBox2="+this.textBox2.Text+"&TextBox3="+this.textBox3.Text+"&TextBox4="+this.textBox4.Text;
ASCIIEncoding encoding=new ASCIIEncoding();
byte[] byte1=encoding.GetBytes(postData);//最终编码后要上传的数据
// Set the content type of the data being posted.
myRequest.ContentType="application/x-www-form-urlencoded";
myRequest.Method="post";//post上传方式
// Set the content length of the string being posted.
myRequest.ContentLength=postData.Length;
Stream newStream=myRequest.GetRequestStream();
newStream.Write(byte1,0,byte1.Length);