转自：VB.NET发送post请求的三种方式指定发送字符串内容、键值对和json串_vb.net post-CSDN博客
''' <summary>
''' 指定Post地址使用Get 方式获取全部字符串
''' </summary>
''' <param name="url">请求地址</param>
''' <param name="dic">键值对</param>
''' <returns>返回字符串</returns>
''' <remarks></remarks>
Public Function Post(ByVal url As String, ByVal dic As Dictionary(Of String, String)) As String
Dim result As String = ""
Dim req As HttpWebRequest = CType(WebRequest.Create(url), HttpWebRequest)
req.Method = "POST"
req.ContentType = "application/x-www-form-urlencoded;charset=UTF-8"
Dim builder As StringBuilder = New StringBuilder()
Dim i As Integer = 0
For Each item In dic
If i > 0 Then builder.Append("&")
builder.AppendFormat("{0}={1}", item.Key, item.Value)
i += 1
Next
Dim data As Byte() = Encoding.UTF8.GetBytes(builder.ToString())
req.ContentLength = data.Length
Using reqStream As Stream = req.GetRequestStream()
reqStream.Write(data, 0, data.Length)
reqStream.Close()
End Using
Dim resp As HttpWebResponse = CType(req.GetResponse(), HttpWebResponse)
Dim stream As Stream = resp.GetResponseStream()
Using reader As StreamReader = New StreamReader(stream, Encoding.UTF8)
result = reader.ReadToEnd()
End Using
Return result
End Function
''' <summary>
''' 指定Post地址使用Get 方式获取全部字符串
''' </summary>
''' <param name="url">请求地址</param>
''' <param name="content">Post提交数据内容(utf-8编码的)</param>
''' <returns>返回字符串</returns>
''' <remarks></remarks>
Public Function Post(ByVal url As String, ByVal content As String) As String
Dim result As String = ""
Dim req As HttpWebRequest = CType(WebRequest.Create(url), HttpWebRequest)
req.Method = "POST"
req.ContentType = "application/x-www-form-urlencoded"
Dim data As Byte() = Encoding.UTF8.GetBytes(content)
req.ContentLength = data.Length
Using reqStream As Stream = req.GetRequestStream()
reqStream.Write(data, 0, data.Length)
reqStream.Close()
End Using
Dim resp As HttpWebResponse = CType(req.GetResponse(), HttpWebResponse)
Dim stream As Stream = resp.GetResponseStream()
Using reader As StreamReader = New StreamReader(stream, Encoding.UTF8)
result = reader.ReadToEnd()
End Using
Return result
End Function
''' <summary>
''' json串post请求
''' </summary>
''' <param name="url"></param>
''' <param name="postData">json字符串</param>
''' <returns></returns>
''' <remarks></remarks>
Public Function Post(ByVal url As String, ByVal postData As String) As String
Dim result As String = ""
Dim req As HttpWebRequest = CType(WebRequest.Create(url), HttpWebRequest)
req.Method = "POST"
req.Timeout = "800"
req.ContentType = "application/json"
Dim data As Byte() = Encoding.UTF8.GetBytes(postData)
req.ContentLength = data.Length
Using reqStream As Stream = req.GetRequestStream()
reqStream.Write(data, 0, data.Length)
reqStream.Close()
End Using
Dim resp As HttpWebResponse = CType(req.GetResponse(), HttpWebResponse)
Dim stream As Stream = resp.GetResponseStream()
Using reader As StreamReader = New StreamReader(stream, Encoding.UTF8)
result = reader.ReadToEnd()
End Using
Return result
End Function
json串最好新建一个实体类(tip:关键字和属性名冲突,可以中括号括起来声明[属性名]),实体类对象(new class.root)通过Newtonsoft.Json.dll序列化成json
