Question

vb为空输出的问题

我定义一个txt_1，
然后txt_1.text如果为1，则输出为“好”
txt_1.text如果为空，则输出为“请输入数据”
txt_1.text如果输入为非数字，既可能是字母加数字，则输出提示框（即Msgbox）提示“输入不合法”
请问这段程序如何编写，给个提示。谢谢

Answer 1

Private Sub Command1_Click()
If txt_1.Text = "1" Then
MsgBox "好"
End If
If txt_1.Text = "" Then
MsgBox "请输入数据"
Else
If Asc(txt_1.Text) > 57 Or Asc(txt_1.Text) < 48 Then '根据ASCII码值来判断是不是数字Asc函数和ASCII码值，可以到网上查，其中数字0－9的码值为48－57
MsgBox "输入不合法"
End If

End If

End Sub

Answer 2

Private Sub Command1_Click()
If txt_1 = "" Then
Print "请输入数据"
ElseIf Not IsNumeric(txt_1) Then
MsgBox "输入不合法"
ElseIf txt_1 = "1" Then
Print "好"
End If
End Sub

Private Sub Form_Load()
txt_1 = ""
Command1.Caption = "确定"
End Sub

Answer 3

Private Sub command1_click()
If Val(txt_1.Text) = 1 Then
MsgBox "好"
ElseIf Len(txt_1.Text) = 0 Then
MsgBox "请输入数据"
ElseIf IsNumeric(txt_1.Text) = False Then
MsgBox "输入不合法"
End If
End Sub

Answer 4

private sub command1_click()
if txt_1.text=1 then print"好"
if len(txt_1.text)=0 then print "请输入数据"
if isnumeric(txt_1.text)=false then msgbox "输入不合法"
end sub

Answer 5

Private Sub command1_click()
If txt_1.Text = "1" Then
print "好"
ElseIf txt_1.Text = "" Then
print"请输入数据"
ElseIf IsNumeric(txt_1.Text) = False Then
MsgBox "输入不合法"
End If
End Sub

Answer 6

If txt_1.Text = "1" Then Print "好"
If txt_1.Text = "" Then Print "请输入数据"
If Str(Val(txt_1.Text)) <> txt_1.Text Then MsgBox "输入不合法"