关于如何改进此异步周期的问题

Question

嗨，我正在解析 Json API 使用我从 quicktype.io 获得的类文件

Imports System.Runtime.CompilerServices
    Imports Newtonsoft.Json
    Namespace HotBit
        Partial Public Class TradeCollection
            <JsonProperty("error")>
            Public Property [Error] As Object
            <JsonProperty("result")>
            Public Property Result As List(Of Resulta)
            <JsonProperty("id")>
            Public Property Id As Long
        End Class
        Partial Public Class Resulta
            <JsonProperty("id")>
            Public Property Id As Long
            <JsonProperty("time")>
            Public Property Time As Long
            <JsonProperty("price")>
            Public Property Price As String
            <JsonProperty("amount")>
            <JsonConverter(GetType(ParseStringConverter))>
            Public Property Amount As Long
            <JsonProperty("type")>
            Public Property Type As TypeEnum
        End Class
        Public Enum TypeEnum
            Buy
            Sell
        End Enum
        Partial Public Class TradeCollection
            Public Shared Function FromJson(ByVal json As String) As TradeCollection
                Return JsonConvert.DeserializeObject(Of TradeCollection)(json, Settings)
            End Function
        End Class
        Public Module Serialize
            <Extension()>
            Public Function ToJson(ByVal self As TradeCollection) As String
                Return JsonConvert.SerializeObject(self, Settings)
            End Function
        End Module
        Friend Module Converter
            Public ReadOnly Settings As JsonSerializerSettings = New JsonSerializerSettings With {
                .MetadataPropertyHandling = MetadataPropertyHandling.Ignore,
                .DateParseHandling = DateParseHandling.None
            }
        End Module
        Friend Class ParseStringConverter
            Inherits JsonConverter
            Public Overrides Function CanConvert(ByVal t As Type) As Boolean
                Return t Is GetType(Long) OrElse t Is GetType(Long?)
            End Function
            Public Overrides Function ReadJson(ByVal reader As JsonReader, ByVal t As Type, ByVal existingValue As Object, ByVal serializer As JsonSerializer) As Object
                If reader.TokenType = JsonToken.Null Then Return Nothing
                Dim value = serializer.Deserialize(Of String)(reader)
                Dim l As Long
                If Long.TryParse(value, l) Then
                    Return l
                End If
                Throw New Exception("Cannot unmarshal type long")
            End Function
            Public Overrides Sub WriteJson(ByVal writer As JsonWriter, ByVal untypedValue As Object, ByVal serializer As JsonSerializer)
                If untypedValue Is Nothing Then
                    serializer.Serialize(writer, Nothing)
                    Return
                End If
                Dim value = CLng(untypedValue)
                serializer.Serialize(writer, value.ToString())
                Return
            End Sub
            Public Shared ReadOnly Singleton As ParseStringConverter = New ParseStringConverter()
        End Class
        Friend Class TypeEnumConverter
            Inherits JsonConverter
            Public Overrides Function CanConvert(ByVal t As Type) As Boolean
                Return t Is GetType(TypeEnum) OrElse t Is GetType(TypeEnum?)
            End Function
            Public Overrides Function ReadJson(ByVal reader As JsonReader, ByVal t As Type, ByVal existingValue As Object, ByVal serializer As JsonSerializer) As Object
                If reader.TokenType = JsonToken.Null Then Return Nothing
                Dim value = serializer.Deserialize(Of String)(reader)
                Select Case value
                    Case "buy"
                        Return TypeEnum.Buy
                    Case "sell"
                        Return TypeEnum.Sell
                End Select
                Throw New Exception("Cannot unmarshal type TypeEnum")
            End Function
            Public Overrides Sub WriteJson(ByVal writer As JsonWriter, ByVal untypedValue As Object, ByVal serializer As JsonSerializer)
                If untypedValue Is Nothing Then
                    serializer.Serialize(writer, Nothing)
                    Return
                End If
                Dim value = CType(untypedValue, TypeEnum)
                Select Case value
                    Case TypeEnum.Buy
                        serializer.Serialize(writer, "buy")
                        Return
                    Case TypeEnum.Sell
                        serializer.Serialize(writer, "sell")
                        Return
                End Select
                Throw New Exception("Cannot marshal type TypeEnum")
            End Sub
            Public Shared ReadOnly Singleton As TypeEnumConverter = New TypeEnumConverter()
        End Class
    End Namespace

在我得到的计时器里面

CronologiaTrades.Stop()
                    ' Dim downloadTasks As New List(Of Task(Of String))
                    Dim s = Await wc.DownloadStringTaskAsync(TextBox1.Text)     'https://api.hotbit.io/api/v1/market.deals?market=KIBA/USDT&limit=150&last_id=1521100930
                    '  downloadTasks.Add(s)
                    'Await Task.WhenAll(downloadTasks)
                    Dim tc = TradeCollection.FromJson(s)
                    RichTextBox4.Clear()
                        For Each r As Resulta In tc.Result
                            RichTextBox4.Text &= UnixTimeStampToDateTime(CDbl(r.Time)).ToString("HH:mm:ss") & " - " & r.Amount.ToString() & " - " & r.Price.ToString() & " - " & r.Type.ToString() & vbCr
                        Next
                    CronologiaTrades.Start()
                Else
                End If
            End If

它使用该函数将 unix 时间戳转换为 HH-mm-ss

Public Shared Function UnixTimeStampToDateTime(ByVal unixTimeStamp As Double) As DateTime
        Dim dtDateTime As System.DateTime = New DateTime(1970, 1, 1, 0, 0, 0, 0, System.DateTimeKind.Utc)
        dtDateTime = dtDateTime.AddSeconds(unixTimeStamp).ToLocalTime()
        Return dtDateTime
    End Function

一切正常，但我可以看到表单在每个刻度（1 秒）处“阻塞”。 我的意思是，我对它的工作原理并不感到失望，但我基本上为其他 3 个类似的 API（来自 Quicktype.io 的类文件，相同的 WebClient 代码 ecc）做同样的工作，当它们运行时，我不' 没有看到这种“形式阻塞”。 我想问您在哪里可以改进我的代码，以便使其在不冻结表单的情况下运行，即使是瞬间。 这是我录制的 gif，它显示了其他人如何工作以及如何创建块。 虽然只是几毫秒的事情，但是看着却很烦人。 （这可能是函数 UnixTimeStampToDateTime 没有以异步方式运行？如果是，我怎样才能使其异步？） 编辑：我尝试删除对 rtb 中函数的调用，并且“gui 块”减少更多，但仍然存在。 谢谢 Gif updated，显示了使用和不使用 unixtimestamptodatetime 函数的行为。 Note：此问题总结整理于How to improve this async cycle

Answer 1

你好

过于频繁地修改 RichTextBox 的内容会导致“gui 块”。 您可以尝试以下代码来连接字符串，然后将其填充到 RichTextBox 中。

    Private Async Sub CronologiaTrades_Tick(sender As Object, e As EventArgs) Handles CronologiaTrades.Tick  
        CronologiaTrades.Stop()  

  
        ' Dim downloadTasks As New List(Of Task(Of String))  
        Dim s = Await wc.DownloadStringTaskAsync("https://api.hotbit.io/api/v1/market.deals?market=KIBA/USDT&limit=150&last_id=1521100930")     'https://api.hotbit.io/api/v1/market.deals?market=KIBA/USDT&limit=150&last_id=1521100930  
        '  downloadTasks.Add(s)  
        'Await Task.WhenAll(downloadTasks)  
        Dim tc = TradeCollection.FromJson(s)  
        Dim str As String = String.Empty  
        For Each r As Resulta In tc.Result  

  
            str &= UnixTimeStampToDateTime(CDbl(r.Time)).ToString("HH:mm:ss") & " - " & r.Amount.ToString() & " - " & r.Price.ToString() & " - " & r.Type.ToString() & vbCr  

  
        Next  
        RichTextBox4.Text = str  
        CronologiaTrades.Start()  
    End Sub  

希望这会有所帮助。

---

如果答案是正确的，请点击“接受答案”并点赞。 如果您对此答案还有其他疑问，请点击“评论”。

注意：如果您想接收相关电子邮件，请按照我们的文档中的步骤启用电子邮件通知 此线程的通知。