哪些是对象，哪些不是
编号：QA000676
建立日期: 1999年3月23日 最后修改日期：1999年3月23日
所属类别：
wy:
Vb5
win95
我对对象的概念很模糊，现在还分不清哪些是对象。现在有一计算器小程序，你能告诉我程序中哪些部分是对象吗？
Dim Num1, Num2 As Single
Dim StrNum1, StrNum2 As String
Dim FirstNum As Boolean
Dim PointFlag As Boolean
Dim Runsign As Integer '储存运算符号
Dim SignFlag As Boolean '判断是否已有运算符号
Private Sub Command1_Click(Index As Integer)
Select Case Index
Case 0 To 9
If FirstNum Then
StrNum1 = Str(Index) '实型转字符型
FirstNum = False '初赋值为假
Else '非初赋值
StrNum1 = StrNum1 + Str(Index)
End If
Text1.Text = StrNum1 '显示
Case 10
If Not PointFlag Then '如果没有小数点
If FirstNum Then '如果是第一个字符
StrNum1 = "0."
FirstNum = False
Else
StrNum1 = StrNum1 + "."
End If
Else '已有小数点
Exit Sub '则退出单击事件
End If
PointFlag = True
Text1.Text = StrNum1
Case 12 To 15
FirstNum = True '使下一次可以输入新数据
PointFlag = False '还原标记值
If SignFlag Then '前面已有运算符未运算
Call Run
Else
SignFlag = True
StrNum2 = StrNum1 '把字符串1复制给字符串2
StrNum1 = "" '字符串1清空
End If
Runsign = Index - 11 '储存键入的运算符
PointFlag = True
Text1.Text = StrNum1
Case 11
If Not SignFlag Then
Text1.Text = StrNum1
equal = Val(StrNum1)
FirstNum = True
PointFlag = False
Else
Call Run
SignFlag = False
End If
Case Else '清除按钮
Call ClearData
End Select
End Sub
Private Sub Form_Load()
Num1 = 0
Num2 = 0
StrNum1 = ""
StrNum2 = ""
FirstNum = True
PointFlag = False
Runsign = 0
SignFlag = False
End Sub
Sub Run()
Num1 = Val(StrNum2)
Num2 = Val(StrNum1)
Select Case Runsign
Case 1 '加
equal = Num1 + Num2
Case 2 '减
equal = Num1 - Num2
Case 3 '乘
equal = Num1 * Num2
Case 4 '除
equal = Num1 / Num2
End Select
StrNum2 = Str(equal)
StrNum1 = StrNum2
Text1.Text = StrNum2
End Sub
Sub ClearData()
Num1 = 0
Num2 = 0
StrNum1 = ""
StrNum2 = ""
FirstNum = True
PointFlag = False
Runsign = 0
SignFlag = False
Text1.Text = "0."
End Sub
回答:
其实判断是否是对象很简单。一个对象应该具有属性或者方法。在你这段代码中，Command1、Form1都具有属性，它们是对象。Click、Load分别是Command1和Form1的事件。ClearData是过程。留个练习题，Text1是对象吗？
此问题由李海回答。
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