通過javascript從json字符串中提取值

Question

我有一個Web服務，該服務以JSON返回結果。在Javascript中，我想遍歷這些結果，以便將其顯示給用戶。

我定義了以下類：

Public Class PointsOfInterest
    Public Property hotspots() As List(Of Hotspot)
        Get
            Return m_hotspots
        End Get
        Set(value As List(Of Hotspot))
            m_hotspots = value
        End Set
    End Property
    Private m_hotspots As List(Of Hotspot)
    Public Property errorString() As String
        Get
            Return m_errorString
        End Get
        Set(value As String)
            m_errorString = value
        End Set
    End Property
    Private m_errorString As String
    Public Property errorCode() As Integer
        Get
            Return m_errorCode
        End Get
        Set(value As Integer)
            m_errorCode = value
        End Set
    End Property
    Private m_errorCode As Integer
End Class

Public Class Hotspot
    Private m_id As String
    Public Property id() As String
        Get
            Return m_id
        End Get
        Set(value As String)
            m_id = value
        End Set
    End Property

    Public Property anchor() As anchor
        Get
            Return m_anchor
        End Get
        Set(value As anchor)
            m_anchor = value
        End Set
    End Property
    Private m_anchor As anchor


    Public Property text() As textprop
        Get
            Return _text
        End Get
        Set(value As textprop)
            _text = value
        End Set
    End Property
    Private _text As textprop


    Public Property imageURL() As String
        Get
            Return _imageURL
        End Get
        Set(value As String)
            _imageURL = value
        End Set
    End Property
    Private _imageURL As String

    Public Property actions() As List(Of action)
        Get
            Return _actions
        End Get
        Set(value As List(Of action))
            _actions = value
        End Set
    End Property
    Private _actions As List(Of action)

End Class

Public Class anchor
    Public Property geolocation() As geoloc
        Get
            Return _geoloc
        End Get
        Set(value As geoloc)
            _geoloc = value
        End Set
    End Property
    Private _geoloc As geoloc

End Class

Public Class textprop
    Public Property title() As String
        Get
            Return _title
        End Get
        Set(value As String)
            _title = value
        End Set
    End Property
    Private _title As String
    Public Property description() As String
        Get
            Return _description
        End Get
        Set(value As String)
            _description = value
        End Set
    End Property
    Private _description As String
    Public Property footnote() As String
        Get
            Return _footnote
        End Get
        Set(value As String)
            _footnote = value
        End Set
    End Property
    Private _footnote As String

End Class


Public Class geoloc
    Public Property lat() As String
        Get
            Return _lat
        End Get
        Set(value As String)
            _lat = value
        End Set
    End Property
    Private _lat As String
    Public Property lon() As String
        Get
            Return _lon
        End Get
        Set(value As String)
            _lon = value
        End Set
    End Property
    Private _lon As String
End Class

Public Class action
    Public Property uri() As String
        Get
            Return _uri
        End Get
        Set(value As String)
            _uri = value
        End Set
    End Property
    Private _uri As String

    Public Property label() As String
        Get
            Return _label
        End Get
        Set(value As String)
            _label = value
        End Set
    End Property
    Private _label As String
    Public Property contentType() As String
        Get
            Return _contentType
        End Get
        Set(value As String)
            _contentType = value
        End Set
    End Property
    Private _contentType As String
    Public Property method() As String
        Get
            Return _method
        End Get
        Set(value As String)
            _method = value
        End Set
    End Property
    Private _method As String
    Public Property activityType() As Integer
        Get
            Return _activityType
        End Get
        Set(value As Integer)
            _activityType = value
        End Set
    End Property
    Private _activityType As Integer
    Public Property showActivity() As Boolean
        Get
            Return _showActivity
        End Get
        Set(value As Boolean)
            _showActivity = value
        End Set
    End Property
    Private _showActivity As Boolean
    Public Property activityMessage() As String
        Get
            Return _activityMessage
        End Get
        Set(value As String)
            _activityMessage = value
        End Set
    End Property
    Private _activityMessage As String

End Class   

我通過JSON通過網絡服務返回了這些信息： http ://www.wunderwedding.com/weddingservice.svc/api/?t = 1&cid = 1&pid=6&lat=52&lng =5& d=10000&city=nijmegen&field1 =0& field2=0&field3 =0& field4=0&hasphoto = 0＆hasvideo = 0＆minrating = 0＆lang = nl

現在，例如，如果我想讀取第三個結果的tel屬性（在本例中為0348551532），我將如何處理？ 就像XSLT一樣，我可以在其中使用表達式進行選擇嗎？

Answer 1

在JavaScript中，我假設您使用支持AJAX的jQuery或ExtJS之類的東西。 一旦在客戶端獲得了JSON，就可以解碼Web服務結果（如果在沒有特殊工具包的情況下讀取JSON，則可以使用Ext.decode或eval（“”））。

JSON解碼后，就可以在JavaScript中使用。

例：

var json = [Function that decodes JSON text];
var uriInfo = json.hotspots[2].actions[1].uri;

如果您使用的是FireFox，則可以安裝一個名為FireBug的插件。 這將使您能夠完成此類事情。 使用該工具，您可以調用console.dir（json）;。 在JavaScript中，並查看javascript等所看到的整個結構。