如何使用VB编写一个在文本里面查找相同的文字的代码

Question

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额.. 就是在一个文本文档里面找出相同的字或者词.

代码怎么写~?
C也行///
这是我编的....我知道有很多错误的地方.希望知道的能指出来...

Private Sub Command1_Click() ←我用VBmini编的,它说这里类型不匹配...
Dim a$, b$, m$, n$(), x$()
a = Trim(Text1.Text)
b = ""
For k = 1 To Len(a)
m = Trim(Mid(a, k, 1))
n(d) = n(d) & m
If m = " " Then d = d + 1

Next k
For kk = 1 To d
For kkk = 1 To d
If n(kk) = n(kk + kkk) Then x(kk) = n(kk)

Next kkk
Next kk
Text2.Text = n & " "
End Sub

Answer 1

Private Sub Command1_Click()
Dim str As String
Dim s As String
s = Text1.Text
For i = 1 To Len(s) - 1
For j = i + 1 To Len(s)
If Mid(s, i, 1) = Mid(s, j, 1) Then str = str & Mid(s, i, 1)
Next
Next
Text2.Text = str
End Sub