一、文本框限定

1、限定輸入的字符長度

文本框中有個MaxLength屬性，輸入自己要限定的數(shù)字即可；也可以利用代碼來限定，當(dāng)超過限定長度時，彈出警告對話窗

Private sub txtUserName_change()If Len(Trim(txtUserName)) > 4?thenMsgBox "姓名不能超過4個字符，請重新輸入!", 0 + 48txtUserName = ""End if? End iSub

Trim函數(shù)是消除字符串的空格，Len函數(shù)是計(jì)算字符串的長度

2、限定特殊字符

Private Sub txtUserName_Change()If Len(Trim(txtUserName)) > 4 thenMsgBox "姓名不能超過4個字符，請重新輸入!", 0 + 48txtUserName = ""End if End sub

3、限定輸入的字符類型

Private Sub txtSID_KeyPress(KeyAscii As Integer)Const xStr As String = "123456" '只能輸入數(shù)字KeyAscii = IIf(Instr(xStr & Chr(8), Chr(KeyAscii)), KeyAscii, 0) End Sub

4、限定特殊字符

Private Sub txtDirector_KeyPress(KeyAscii As Integer)Select Case KeyAsciiCase 8 '限制退格鍵Case Asc("A") To ("Z")Case Asc("a") To ("z")Case Is < 0Case ElseKeyAscii = 0MsgBox "格式錯誤，請輸入漢字或英文!", 0 + 48txtDirector.Text = ""End Select End Sub

5、只能輸入數(shù)字

If keyAscii = 8 Then Exit Sub If keyAscii < 48 Or keyAscii > 57 Then keyAscii = 0

6、限制數(shù)字大小，這個適合成績對話框

Private Sub txtResult_change() On Error Resume Next If Val(Trim(txtResult.Text)) > 100 Then MsgBox "輸入數(shù)字過大，請重新輸入" txtResult.Text = "" End If End Sub

?7、不能輸入特殊字符(和第二、四個一樣的性質(zhì)）

Select Case keyAscii Case -20319 To -3652 Case 48 To 57 Case 65 To 98 Case 97 To 122 Case 8 Case Else keyAscii = 0 End Select

?8、限定特殊字符、數(shù)字、空格，只能輸入漢字和字母

Private Sub txtCourseName_KeyPress(KeyAscii As Integer)If KeyAscii < 0 or KeyAscii = 8 or KeyAscii = 13 ThenElse IfNot chr(KeyAscii) Like "[a-ZA-Z]" ThenkeyAscii = 0End if End sub

二、下拉框限定?

Combox限定不能鍵盤輸入，只能選擇下拉框里面的內(nèi)容

Private Sub comboGrade_KeyPress(KeyAscii As Integer)KeyAscii = 0 '限制鍵盤不能輸入內(nèi)容 End Sub

三、限定成績

Private Sub txtResult_Change()If Val(txtResult.Text) > 120 Or Val(txtResult.Text) < 0 ThenMsgBox "請輸入成績在0~120范圍內(nèi)!", 0 + 48txtResult.Text = ""End If End Sub

四、限定不能復(fù)制粘貼

在第二次輸入密碼時，不能復(fù)制粘貼

Private Sub txtPassword1_KeyDown(KeyCide As Integer, Shift As Integer)If (KeyCode = 86 Or KeyCode = 67 Or KeyCode = 88) And Shift = 2 ThenMsgBox "不能復(fù)制粘貼", 0 + 48txtPassword1.Text = ""End If End Sub

提示密碼剩余次數(shù)

If miCout = 1 ThenMsgBox "您還有兩次機(jī)會", 0 + 48,"提示" Exit sub End IfIf miCout = 2 ThenMsgBox "您還有一次機(jī)會", 0 + 48,"提示" Exit sub End IfIf miCout = 3 ThenMsgBox "即將關(guān)閉程序", 0 + 48,"提示"Me.Hide Exit sub End If

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