很多编程爱好者在VB的API编程中经常遇到API调用中的错误代码(Error Code,在API调用中 遇到错误时使用GetLastError函数可以得到)。但是很多的时候错误代码并没有多大用处,因为 你并不知道代码所代表的含义。而实际上,在Windows中为每个错误码提供了一个错误提示,而 且适应不同的语言版本(既如果你使用中文版Windows,提示也是中文的)。只要通过API编程就 可以获得详细的错误提示。 下面通过程序来介绍,运行下面的程序,首先要在Form中加入一个ListBox和CommandButton 在将下面的代码加入到form的代码窗口中。 Private Declare Function FormatMessage Lib "kernel32" _ Alias "FormatMessageA" (ByVal dwFlags As Long, _ lpSource As Any, ByVal dwMessageId As Long, _ ByVal dwLanguageId As Long, ByVal lpBuffer _ As String, ByVal nSize As Long, Arguments As _ Long) As Long Private Declare Function GetLastError Lib "kernel32" _ () As Long Private Declare Function CloseHandle Lib "kernel32" _ (ByVal hObject As Long) As Long
Const FORMAT_MESSAGE_FROM_SYSTEM = &H1000 Const FORMAT_MESSAGE_IGNORE_INSERTS = &H200
Private Sub Command1_Click() Dim ErrID As Long Dim astr As String Dim bstr As String Dim l As Long astr = String$(256, 20) '获得具体的错误信息 For ErrID = 0 To 8191 l = FormatMessage(FORMAT_MESSAGE_FROM_SYSTEM Or _ FORMAT_MESSAGE_IGNORE_INSERTS, 0&, ErrID, 0&, _ astr, Len(astr), ByVal 0) If l Then bstr = Left$(astr, InStr(astr, Chr(10)) - 2) '将错误信息加入列表框 List1.AddItem Str(ErrID) + " " + bstr End If Next ErrID End Sub 运行程序,点击Command1,错误代码和向对应的错误提示信息就全部列在ListBox中了。 以上程序在Win95,VB5.0下运行通过。
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