函数总是返回布尔值False

我有以下function：

Function IsInArray(ByVal needle As String, haystack() As String) As Boolean Dim element As Variant For Each element In haystack If element = needle Then IsInArray = True End If Next element IsInArray = False End Function 

我通过这个子程序调用：

 Sub CallIsInArray() Dim haystack(1 To 4) As String haystack(1) = "T1" haystack(2) = "T2" haystack(3) = "T3" haystack(4) = "T4" Dim needle As String needle = "T1" ' Should return True but instead of it return False ' needle = "T1x" ' Return False as expected Dim result As Boolean result = IsInArray(needle, haystack) MsgBox result End Sub 

问题是IsInArray总是返回False ，为什么？

Answer 1

findneedle时忘了返回（ Exit Function ）。

 Function IsInArray(ByVal needle As String, haystack() As String) As Boolean Dim element As Variant For Each element In haystack If element = needle Then IsInArray = True Exit Function End If Next element IsInArray = False End Function