Question

vb中显示“下标越界”是什么意思？为什么我这个程序总会显示下标越界？谢谢

Dim a(1 To 10)
Private Sub Command1_Click()
Print "排序前：";
For i = 1 To 10

a(i) = Int(Rnd * 100 + 1)
Next i
For i = 1 To 10
Print a(i);
Next i

End Sub
Private Sub Command2_Click()
Print "排序后：";
For i = 1 To 10
For j = i To 1 Step -1
If a(j) < a(j + 1) Then
t = a(j)
a(j) = a(j + 1)
a(j + 1) = t
End If
Next j
Print
Next i
For i = 1 To 10
Print a(i);
Next i
End Sub

Answer 1

当j=10时，a(j + 1)=a(11)，这就超出数组a的下标范围了，所以提示你“下标越界”。应该把排序的代码改为：
Private Sub Command2_Click()
Print "排序后："
For i = 1 To 9
For j = i + 1 To 10
If a(i) < a(j) Then
t = a(i)
a(i) = a(j)
a(j) = t
End If
Next j
Next i
For i = 1 To 10
Print a(i);
Next i
End Sub