用vb编写计算器(与小键盘响应)(修改).doc

用vb编写计算器(与小键盘响应)(修改)Option Explicit Dim lastinput As String 指示上一次按键事件的类型 Dim num1 As Double 第一个操作数 Dim num2 As Double 第二个操作数 Dim opttype As Integer 按了那个符号 Dim keynum As Integer Dim result As Double 表示运算结果 Private Sub Command1_Click(Index As Integer) 当按下数字键（0-9）时，在文本框尾部追加数据 并通过变量lastinput记录上次按键为数字键 If Len(Text1.Text) 16 Then Exit Sub If Text1.Text = 0 Or lastinput = eqv Then Text1.Text = Text1.Text = Text1.Text & Index 追加数据 lastinput = num If keynum = 48 And keynum 0 Then Text1.Text = Sqr(Val(Text1.Text) 运用Sqr函数 Else MsgBox 被开方数不能为负数, 0 + 48, 提示信息 被开方数为负数时提示错误 Text1.Text = 清零 Text1.SetFocus 焦点 End IfEnd SubPrivate Sub Command12_Click() OFF按钮 End 退出程序End SubPrivate Sub Command2_Click() 小数点 如果数据位数超出范围或数据中已包含小数点，退出本过程 If Len(Text1.Text) 16 Or InStr(1, Text1.Text, .) 0 And lastinput eqv Then Exit Sub 若以0开始输入，在“0”前加0 若在数据尾部输入过程中按下“.”，直接将“.”追加在数据尾部 If lastinput = opt Or lastinput = eqv Or lastinput = neg Then Text1.Text = Text1.Text + 0. Else Text1.Text = Text1.Text + . End If lastinput = numEnd SubPrivate Sub Command3_Click() C按钮，每次退一个数字If Len(Text1.Text) = 1 Then Text1.Text = Left(Text1.Text, Len(Text1.Text) - 1) Else MsgBox 已经是最后一位了, 0 + 48, 提示信息 End IfEnd SubPrivate Sub Command4_Click() DEL按钮 重新设置并初始化变量 num1 = 0 num2 = 0 Text1.Text = 0 opttype = -1 lastinput = numEnd SubPrivate Sub Command5_Click(Index As Integer) 加减乘除号 按下运算符键后，获取第一个操作数num1，并记录按下的运算符 num1 = Val(Text1.Text) Text1.Text = lastinput = opt opttype = IndexEnd SubPrivate Sub Command6_Click() 等号结果 num2 = Val(Text1.Text) Select Case opttype Case 0 result = num1 + num2 加法运算 Case 1 result = num1 - num2 减法运算 Case 2 result = num1 * num2 乘法运算 Case 3 除法运算 If num2 = 0 Then Text1.Text = .E MsgBox 输入数据不能为0, 0 + 48, 提示 除数为0时提示错误 Else result = num1 / num2 End If End Select If Text1.Text .E Then Text1.Text = Trim(Str(result) 结束本次计算，重新赋值 num1 = 0 num2 = 0 lastinput = eqv opttype = -1End SubPrivate Sub Command7_Click() Backspace按钮，退格的作用If Len(Text1.Text) = 1 Then Text1.Text = Left(Text1.Text, Len(Text1.Text) - 1) Else MsgBox 已经是最后一位了, 0 + 48, 提示信息 End IfEnd SubPrivate Sub Command8_Click() 正负号转换Text1.Text = Trim(Str(-Val(Text1.Text)End SubPrivate Sub Command9_Click() 倒数按钮 If Text1.Text = 0 Then 0没有倒数 MsgBox 数据输入不正确, 0 + 48, 错误提示 Else Text1.Text = 0 & 1 / Val(Text1.Text) End IfEnd SubPrivate Sub Form_KeyPress(KeyAscii As Integer) 与小键盘响应 Dim i As Integer 定义i 下面程序里的Beep使你按下键盘时发出声音 If KeyAscii = Asc(0) Then 数字键0 i = 0 Command1_Click (i) Beep ElseIf KeyAscii = Asc(1) Then 数字键1 i = 1 Command1_Click (i) Beep ElseIf KeyAscii = Asc(2) Then 数字键2 i = 2 Command1_Click (i) Beep ElseIf KeyAscii = Asc(3) Then 数字键3 i = 3 Command1_Click (i) Beep ElseIf KeyAscii = Asc(4) Then 数字键4 i = 4 Command1_Click (i) Beep ElseIf KeyAscii = Asc(5) Then 数字键5 i = 5 Command1_Click (i) Beep ElseIf KeyAscii = Asc(6) Then 数字键6 i = 6 Command1_Click (i) Beep ElseIf KeyAscii = Asc(7) Then 数字键7 i = 7 Command1_Click (i) Beep ElseIf KeyAscii = Asc(8) Then 数字键8 i = 8 Command1_Click (i) Beep ElseIf KeyAscii = Asc(9) Then 数字键9 i = 9 Command1_Click (i) Beep ElseIf KeyAscii = Asc(+) Then 加号按键 i = 0 Command5_Click (i) Beep ElseIf KeyAscii = Asc(-) Then 等号按键 i = 1 Command5_Click (i) Beep ElseIf KeyAscii = Asc(*) Then 乘号按键 i = 2 Command5_Click (i) Beep ElseIf KeyAscii = Asc(/) Then 除号按键 i = 3 Command5_Click (i) Beep ElseIf KeyAscii = Asc(=) Then 等号按键 Command6_Click Beep ElseIf KeyAscii = Asc(.) Then 小数点按键 Command2_Click Beep End IfEnd SubPrivate Sub F