json - 计算循环中值的出现次数

Question

我正在读取返回日期的 Json 数组。

我想做的是遍历 Json 数组，存储发生的日期，并计算每个日期发生的次数。

       Using client As New WebClient
            Dim feedResponse As String = client.DownloadString(Url)
            Dim jsonObject As Object = JSONHelper.Deserialize(feedResponse)
            Dim feedArray As JArray = JSONHelper.readJSonArray(jsonObject, "data")

                For i = 0 To feedArray.Count - 1
                    Dim feedDetailsObject As Object = feedArray.ElementAt(i)
                    Dim feeddate = JSONHelper.readJSonElement(feedDetailsObject, "updated_time").ToShortDateString
                Next

            End If
        End Using

我想计算“feeddate”值出现了多少次。

计算循环中相同值出现次数的最佳方法是什么？

Answer 1

您可以使用 LINQ 的 GroupBy 来计算每个 updated_time 值的出现次数:

Dim groupedDates = feedArray.GroupBy(Function(x) JSONHelper.readJSonElement(x, "updated_time").ToShortDateString)
For Each group In groupedDates
    Dim feedDate = group.Key
    Dim numberOfOccurrence = group.Count()
Next