Question

我正在尝试建立一个VB.net网站，以在频道名称旁边显示图像（如果正在直播）。我目前已建立包含URL和图像的页面，并且已经设置了搜索API：

https://www.googleapis.com/youtube/v3/search?part=snippet&channelId=[ChannelID]&type=video&eventType=live&key=[API-KEY]

我知道这是可行的，因为在正常跟随链接时，我会看到JSON。

唯一的问题是我不知道如何在VB中发送HTTP请求。我本来只是在测试时在page_load上执行此请求，但据我所知：

Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
    Dim request As WebRequest = WebRequest.Create("https://www.googleapis.com/youtube/v3/search?part=snippet&channelId=[ChannelID]&type=video&eventType=live&key=[API-KEY]")
End Sub

如何在VB.net中发送此请求？我将如何读取返回的JSON？

Answer 1

我能够将JSON返回到String变量中：

Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
    Dim request As WebRequest = WebRequest.Create("https://www.googleapis.com/youtube/v3/search?part=snippet&channelId=[ChannelID]&type=video&eventType=live&key=[API-KEY]")
    Dim streamReader As System.IO.StreamReader = New System.IO.StreamReader(response.GetResponseStream)

    Dim youtube As String = streamReader.ReadToEnd

    MsgBox(youtube)
End Sub

我已将此功能修改为允许检查任何通道ID的功能。它最初返回了boolean，但我对其进行了调整，使其返回了integer来执行错误处理，而无需修改return语句或后面代码的其他部分中的函数调用。

Protected Function IsLiveStreaming(channelID As String) As Integer

    Try
        Dim request As WebRequest = WebRequest.Create("https://www.googleapis.com/youtube/v3/search?part=snippet&channelId=" & channelID & "&type=video&eventType=live&key=[API-KEY]")

        Dim response As WebResponse = request.GetResponse

        Dim streamReader As System.IO.StreamReader = New System.IO.StreamReader(response.GetResponseStream)
        Dim youtube As String = streamReader.ReadToEnd

        Dim obj As Newtonsoft.Json.Linq.JObject = JObject.Parse(youtube)
        Dim arr As JArray = obj("items")

        If arr.Count > 0 Then
            Return True
        Else
            Return False
        End If
    Catch ex As Exception
        'Typically a 403 error from exceeding quota on YouTube api
        Return -1
    End Try

    Return False

End Function

检查YouTube频道是否正在直播

1 个答案: