专家坐堂-result.GetValue("trade_type")怎么为空了？Foxtable(狐表) - 新一代数据库软件，完美融合Access、Foxpro、Excel、vb.net之优势，人人都能掌握的快速软件开发工具!

-- result.GetValue("trade_type")怎么为空了？

Dim url As String = Functions.Execute("GetApiUrl","api_orderquery")

Dim hc As New HttpClient(url)

hc.C

hc.Timeout = 6

hc.Content = req.ToXML

Dim ret As String = hc.GetData()

If ret= "" Then

Functions.Execute("logtext","订单查询超时没有返回结果.")

Return False

End If

Functions.Execute("logtext","订单查询结果: " & ret)

Dim result As WxPayData = Functions.Execute("GetWxPayData")

result.FromXml(ret)

If result.GetValue("return_code") = "FAIL" Then

Functions.Execute("logtext","订单查询失败: " & result.GetValue("return_msg"))

Return False

End If

Dim dr As DataRow

If tn = "" Then

tn = result.GetValue("trade_type")

End If

上述订单查询结果ret

订单查询结果: <xml><return_code><![CDATA[SUCCESS]]></return_code>

<return_msg><![CDATA[OK]]></return_msg>

<mch_id><![CDATA[1493759122]]></mch_id>

<nonce_str><![CDATA[m9lJXWyyt7B0Iv1m]]></nonce_str>

<result_code><![CDATA[SUCCESS]]></result_code>

<out_trade_no><![CDATA[149375912220181017154926795]]></out_trade_no>

<trade_state><![CDATA[NOTPAY]]></trade_state>

<trade_state_desc><![CDATA[订单未支付]]></trade_state_desc>

</xml>

这是什么原因，没有"trade_type"