Question

在JSON Geocode GetResponse中，Microsoft提供的代码使用函数返回结果。但是，我想在函数之外使用结果，但之后我无法从函数内部访问数据。也许代码可以更清楚地解释这一点：

    Dim geocodeRequest As New Uri(String.Format("http://dev.virtualearth.net/REST/v1/Locations?q={0}&key={1}", query, key))
    Dim latlong_adress As BingMapsRESTService.Common.JSON.Location = Nothing

    GetResponse(geocodeRequest, Function(x)
                                    MsgBox(x.ResourceSets(0).Resources.Length & " result(s) found.")
                                    latlong_adress = x.ResourceSets(0).Resources(0)
                                    'Correct results:
                                    MsgBox(latlong_adress.Confidence)
                                    MsgBox(latlong_adress.EntityType)
                                    MsgBox(latlong_adress.Point.Coordinates(0) & ", " & latlong_adress.Point.Coordinates(1))
                                    Return 0
                                End Function)
    'Empty: --> is nothing
    If latlong_adress IsNot Nothing Then
        MsgBox(latlong_adress.Confidence)
        MsgBox(latlong_adress.EntityType)
        MsgBox(latlong_adress.Point.Coordinates(0) & ", " & latlong_adress.Point.Coordinates(1))
    End If

如何在做出回复后从响应中访问数据？

Answer 1

我解决了我的问题，虽然我不太清楚答案的正确性。我理解该问题的问题与GetResponse操作的异步类型有关。

我添加了一个事件如下：

Public Event NewGeocode(ByVal LocationData As BingMapsRESTService.Common.JSON.Location, ByVal successful As Boolean)
Private Sub geocodeLoop(Optional LocationData As BingMapsRESTService.Common.JSON.Location = Nothing, Optional successfull As Boolean = False) Handles Me.NewGeocode
    If LocationData Is Nothing Then
        geocodeAddress()
    Else
        If successfull = True Then
            'Correct results:
            MsgBox(LocationData.Confidence)
            MsgBox(LocationData.EntityType)
            MsgBox(LocationData.Point.Coordinates(0) & ", " & LocationData.Point.Coordinates(1))
            geocodeAddress()
        Else
            MsgBox("Unsuccessfull")
        End If
    End If
End Sub

Private Sub geocodeAddress()
    Dim key As String = ...
    Dim query As String = "1 Microsoft Way, Redmond, WA"

    Dim geocodeRequest As New Uri(String.Format("http://dev.virtualearth.net/REST/v1/Locations?q={0}&key={1}", query, key))
    Dim latlong_adress As BingMapsRESTService.Common.JSON.Location = Nothing
    GetResponse(geocodeRequest, Function(x)

                                    If Not x.ResourceSets(0).Resources.Length = 0 Then
                                        RaiseEvent NewGeocode(x.ResourceSets(0).Resources(0), True)
                                    Else
                                        RaiseEvent NewGeocode(Nothing, False)
                                    End If
                                    Return 0
                                End Function)
End Sub
Private Sub Button15_Click(sender As Object, e As EventArgs) Handles Button15.Click
    geocodeLoop()
End Sub

在函数内访问变量

1 个答案: