POST变量到Web服务器?

时间:2010-05-03 18:53:52

标签: vb.net post webforms

我一直在尝试Google的一些事情,将数据发布到网络服务器,但它们都不起作用:我仍然坚持如何将变量转换为请求,考虑到第二个变量是一个SQL查询所以它有空格。

有人知道使用WebClient POST数据的正确方法吗?我宁愿使用WebClient,因为它需要的代码少于HttpWebRequest / HttpWebResponse。

这是我到目前为止所尝试的内容:

Private Sub Button1_Click(ByVal sender As System.Object,ByVal e As System.EventArgs)Handles Button1.Click         Dim wc = New WebClient()

    ''#convert data
    wc.Headers.Add("Content-Type", "application/x-www-form-urlencoded")
    Dim postData = String.Format("db={0}&query={1}", _
                                 HttpUtility.UrlEncode("books.sqlite"), _
                                 HttpUtility.UrlEncode("SELECT id,title FROM boooks"))

    ''#Dim bytArguments As Byte() = Encoding.ASCII.GetBytes("db=books.sqlite|query=SELECT * FROM books")

    ''#POST query
    Dim bytRetData As Byte() = wc.UploadData("http://localhost:9999/get", "POST", postData)
    RichTextBox1.Text = Encoding.ASCII.GetString(bytRetData)

    Exit Sub

    Dim client = New WebClient()

    Dim nv As New Collection
    nv.Add("db", "books.sqlite")
    nv.Add("query", "SELECT id,title FROM books")

    Dim address As New Uri("http://localhost:9999/get")

    ''#Dim bytRetData As Byte() = client.UploadValues(address, "POST", nv)

    RichTextBox1.Text = Encoding.ASCII.GetString(bytRetData)

    Exit Sub

    ''#Dim wc As New WebClient()

    ''#convert data
    wc.Headers.Add("Content-Type", "application/x-www-form-urlencoded")
    Dim bytArguments As Byte() = Encoding.ASCII.GetBytes("db=books.sqlite|query=SELECT * FROM books")

    ''#POST query
    ''#Dim bytRetData As Byte() = wc.UploadData("http://localhost:9999/get", "POST", bytArguments)
    RichTextBox1.Text = Encoding.ASCII.GetString(bytRetData)

    Exit Sub
End Sub

谢谢。


编辑:感谢大家的反馈。

对于那些有同样问题的人,这里有一些工作代码:

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
    Dim baseURL As String = "localhost:9999"
    Dim strURL As String = "http://" & baseURL & "/get"

    Dim client As New WebClient()

    client.Headers.Add("Content-Type", "application/x-www-form-urlencoded")
    client.Headers.Add("Accept-Encoding", "text/plain")
    client.Headers.Add("User-Agent", "Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US) AppleWebKit/532.9 (KHTML, like Gecko) Iron/4.0.280.0 Chrome/4.0.280.0 Safari/532.9")
    'BAD client.Headers.Add("Host", baseURL)
    'BAD client.Headers.Add("Host", "localhost")

    'Convert in parameters in case contain spaces, accents, etc.
    Dim postData As String = String.Format("db={0}&query={1}", _
                         HttpUtility.UrlEncode("books.sqlite"), _
                         HttpUtility.UrlEncode("SELECT id,title FROM books"))

    RichTextBox1.Text = client.UploadString(New Uri(strURL), "POST", postData)
End Sub

1 个答案:

答案 0 :(得分:3)

由于您使用“localhost”作为Web客户端的目标,我将假设您也控制此站点。通过该站点的查询字符串接受SQL是一个非常糟糕的主意。

然后,您的问题的答案是重新编写您的网站,以便它只希望参数插入查询而不是查询本身。

您的代码存在其他一些问题:

  • WebClient实现IDisposable,因此应使用using block
  • 创建
  • 我认为UploadData()可能是错误的调用函数 - 你期望来自服务器的响应,不是吗?尝试使用DownloadString();它仍会发布您的数据。
  • 我会给你怀疑的好处,并假设“Exit Sub”行有调试,但值得一提的是断点会更好地为你服务。