求助好人帮帮忙

Private Sub Command1_Click()
Dim z1, z2, z3, z4, z5 As Double
z1 = Val(txts.Text)
z2 = 1
z3 = 10
z4 = 20
For i = z2 To z3   ' 第一个循环
z1 = z1 + 1
Open App.Path + "\jiafa.txt" For Append As #1
     Print #1, z1
   Close #1
Next
For i= z1 To z4 Step 2    '第二个循环
z1 = 100 + i
Open App.Path + "\jiafa.txt" For Append As #1
     Print #1, z1
   Close #1
Next
For i= z1 To z3     '第三个循环
z1 = i + 1
Open App.Path + "\jiafa.txt" For Append As #1
     Print #1, z1
   Close #1
Next
End Sub
为什么输出只是第一个循环的结果
第二个和第三个循环为什么不能输出结果？ --------------------编程问答-------------------- 你所使用的是添加记录方式，应该不会有问题啊，文件也正常关闭了。哦，对了，文件号问题：不能使用#1，把这些#1换为：FileNumber，并在最前面定义：
      dim FileNumber as long
     FileNumber=FreeFile '由操作系统动态分配 --------------------编程问答-------------------- 在每一个Open前面加上这一行：
FileNumber=FreeFile   '由操作系统动态分配 --------------------编程问答-------------------- VB不会 --------------------编程问答-------------------- 只用一次Open就行了，干嘛用那么多次，效率也不高，我给你改改
Private Sub Command1_Click()
Dim z1, z2, z3, z4, z5             As Double
z1 = Val(txts.Text)
z2 = 1: z3 = 10: z4 = 20
Open App.Path + "\jiafa.txt" For Append As #1
    For i = z2 + 1 To z3 + 1    '   第一个循环
        Print #1, i
    Next
    For i = z1 + 100 To z4 + 100 Step 2 '第二个循环
        Print #1, i
    Next
    For i = z1 + 1 To z3 + 1    '第三个循环
        Print #1, i
    Next
Close #1
End Sub
--------------------编程问答-------------------- 不知道是不是，但我提醒你一下，如果执行到第二个第三个循环的时候，z1>z3 z4，那么for i = z1 to z4 step 正数就肯定不会被执行

补充：VB ,  基础类