VB程序在Text1中输入一串大写字母组成的字符串，统计A~Z每个大写字母出现的次数，并在List1中输出？

Question

在Text1中输入一串大写字母组成的字符串，统计A~Z每个大写字母出现的次数，并在List1中输出。
思路提示
1. 通过循环取出每一个字符进行判断。可用a(1)~a(26)分别存放A~Z出现的次数，可通过ASC函数进行转换，如将A转换成1，B转换成2……Z转换成26。ASC(“A”)=65。
2. 通过循环输出每一个字符出现次数。可用CHR函数将1~26转换成A~Z。CHR(65)=”A”。

Answer 1

用instr函数可直接得到字母出现的次数，编程比较方便。

Answer 2

Private Sub Command1_Click()
Dim a(65 To 91) As Byte, ichr As String, istr As String
istr = InputBox("enter a string", , "AadfafBCCZDDZZ")
Dim i As Integer
For i = 1 To Len(istr)
ichr = Mid(istr, i, 1)
Select Case ichr
Case "A" To "Z"
a(Asc(ichr)) = a(Asc(ichr)) + 1
End Select
Next
For i = 65 To 91
If a(i) <> 0 Then List1.AddItem Chr(i) & a(i)
Next

End Sub

Answer 3

Private Sub Command1_Click()Dim a As Integer, e As Integer, z As Integer, c As String, i As IntegerFor i = 1 To Len(Text1.Text) c = LCase(Mid(Text1.Text, i, 1)) If c = "a" Then a = a + 1
If c = "b" Then a = a + 1
.
.
.<此处写b-x>
.
.
If c = "x" Then e = e + 1
If c = "y" Then e = e + 1 If c = "z" Then z = z + 1NextMsgBox "a次数" & a & vbCrLf & "e次数" & e & vbCrLf & "z次数" & zEnd Sub