创建永久二维码

永久二维码，是无过期时间的，但数量较少（目前为最多10万个）。

创建永久二维码的代码参考：

Dim url As String = "https://api.weixin.qq.com/cgi-bin/qrcode/create?access_token={0}"
Dim hc As New HttpClient(CExp(url,Functions.Execute("GetAccessToken")))
Dim jo As New JObject
jo("action_name") = "QR_LIMIT_SCENE" '类型为永久二维码
jo("action_info") = New JObject
jo("action_info")("scene") = New JObject
jo("action_info")("scene")("scene_id") = 112 '指定此二维码的场景ID
hc.Content = jo.ToString()
jo = JObject.Parse(hc.GetData)
If jo("errcode") Is Nothing Then
    Dim dr As DataRow = DataTables("QRCode").AddNew()
    dr("Ticket") = jo("ticket")
    dr("Descripttion") = "永久二维码说明"
    dr.Save()
Else
    MessageBox.Show(jo("errcode"))
End If

永久二维码的场景ID可以是字符串，生成带字符串场景ID的永久二维码的代码可以参考：

Dim url As String = "https://api.weixin.qq.com/cgi-bin/qrcode/create?access_token={0}"
Dim hc As New HttpClient(CExp(url,Functions.Execute("GetAccessToken")))
Dim jo As New JObject
jo("action_name") = "QR_LIMIT_STR_SCENE" '永久二维码,场景ID为字符串
jo("action_info") = New JObject
jo("action_info")("scene") = New JObject
jo("action_info")("scene")("scene_str") = "字符串形式的场景ID" '指定此二维码的场景场景ID
hc.Content = jo.ToString()
jo = JObject.Parse(hc.GetData)
If jo("errcode") Is Nothing Then
    Dim dr As DataRow = DataTables("QRCode").AddNew()
    dr("Ticket") = jo("ticket")
    dr("Descripttion") = "永久二维码说明"
    dr.Save()
Else
    MessageBox.Show(jo("errcode"))
End If

永久二维码的获取和下载，方法和临时二维码完全一致，例如下面的代码同时完成了二维码的生成和下载任务：

Dim url As String = "https://api.weixin.qq.com/cgi-bin/qrcode/create?access_token={0}"
Dim hc As New HttpClient(CExp(url,Functions.Execute("GetAccessToken")))
Dim jo As New JObject
jo("action_name") = "QR_LIMIT_SCENE" '类型为永久二维码
jo("action_info") = New JObject
jo("action_info")("scene") = New JObject
jo("action_info")("scene")("scene_id") = 112 '指定此二维码的场景ID
hc.Content = jo.ToString()
jo = JObject.Parse(hc.GetData)
If jo("errcode") Is Nothing Then
    Dim dr As DataRow = DataTables("QRCode").AddNew()
    dr("Ticket") = jo("ticket")
    dr("Descripttion") = "永久二维码说明"
    dr.Save()
    '下载生成好的二维码
    hc = New HttpClient("https://mp.weixin.qq.com/cgi-bin/showqrcode?ticket=" & dr("Ticket"))
    hc.GetFile("c:\data\qrcode.jpg")
Else
    MessageBox.Show(jo("errcode"))
End If