这样一行一行读取文本文件（txt文件）为何取值不对？急！

一个从数据库导出的文本文件部分数据如下：

num branch vest_in_site
8300207 8295 121
8300241 8295 121
8300242 8295 121
8300245 8295 121
8300247 8295 121

----------------------------------------------------
写如下函数一行一行读取：
Public Function ImportSpeData() As Boolean
Dim a$(), i%, x$, n%, pos%

Dim phsnum As String
Dim bureau As String
Dim channel As String


On Error GoTo errhandle
CommonDialog1.Filter = "txt File|*.txt"
CommonDialog1.ShowOpen
Dim FileName As String

FileName = CommonDialog1.FileName
Text1.Text = FileName
Open FileName For Input As #1 ' 打开文件
Do While Not EOF(1)
Line Input #1, x
'以下循环是将数据间的多个空格压缩成一个空格,因为可能字段值间空格会变
Do
n = Len(x)
x = Replace(x, " ", " ")
Loop While n > Len(x)

If x Like "*[A-Za-z]*" Then '如果含有字母，表示为第一行，是字段名，不处理
Else
a = Split(x, " ") '将数据分割到数组A中
Dim j As Integer
phsnum = a(0) '为什么在这里a(0)的值为一整行的数据，而下面a(1)没值，于是越界退出？
bureau = a(1)
channel = a(2)
End If
Loop
ImportSpeData = True
Close #1
Exit Function
errhandle:
ImportSpeData = False
End Function