第一次按键单击时代码不读取字符串

Question

所以我有这个代码应该检查字符串中的某种类型的文本。如果字符串包含文本，则它将播放.wav文件。通过程序中的按钮单击执行代码。问题是，如果代码存在于字符串中并且我单击按钮，则第一次单击.wav文件时不会播放。但它是第二次点击它播放。这是相关的代码。

Dim htmlsource As String = ""
    htmlsource = WebControl2.ExecuteJavascriptWithResult("document.documentElement.outerHTML") 'Takes HTML code     using javascript
    RichTextBox1.Text = htmlsource.ToString()
    '-----------------------------------

    '---------------text to look for----------------
    Dim TradeOffer1 As String = "<span class=""notification"">"
    Dim TradeCount As Integer = 0
    Dim TradeOffer2 As String = " new offers</span>"
    '-----------------------------------
    '-While loop that searches for text-
    While runloop = True
        If htmlsource.Contains(String.Concat(TradeOffer1, TradeCount, TradeOffer2)) Then
            My.Computer.Audio.Play("C:\Users\Thomas\pling.wav")
            runloop = False
        Else
            TradeCount = TradeCount + 1
        End If
        If TradeCount = 6 Then
            runloop = False
        End If
    End While
    runloop = True
    TradeCount = 0