WinCE.net 调用QueryPerformanceCounter和QueryPerformanceCounter，失败！

tang1117

WinCE.net 调用QueryPerformanceCounter和QueryPerformanceCounter，失败！ [复制链接]

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4. Public Class Form1
   
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6.     Private Declare Function QueryPerformanceCounter Lib "coredll" (ByVal lpPerformanceCount As Long) As Long
   
7.     Private Declare Function QueryPerformanceFrequency Lib "coredll" (ByVal lpFrequency As Long) As Long
   
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10.     Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
    
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12.         Dim l As Long
    
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14.         If QueryPerformanceFrequency(l) Then
    
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16.             TextBox1.Text = l.ToString
    
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18.         End If
    
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20.         If QueryPerformanceCounter(l) Then
    
21.             TextBox1.Text = TextBox1.Text & l.ToString
    
22.         End If
    
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24.     End Sub
    
25. End Class

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为什么 不走If里面走，总是失败（False）啊？

shuiyuntianmo

应该是你的系统没有实现OEM层的OEMQueryPerformanceCounter以及OEMQueryPerformanceFrequency 函数. 而你所使用的函数正是通过以上两个函数的调用来实现的,所以在你调用以后就会返回false..

添加 QueryPerformanceFrequency, QueryPerformanceCounter支持的请参照如下步骤:
1. Provide your own implementations of the OEMQueryPerformanceCounter and OEMQueryPerformanceFrequency functions.
2. Add code to OEMInit to set the variables pQueryPerformanceCounter and pQueryPerformanceFrequency to point to your implementations of the OEMQueryPerformanceCounter and OEMQueryPerformanceFrequency functions.
更详细的说明请参考msdn.