请教各位怎么循环数组

刚开始学习，请教各位大佬怎么循环数组
A1*1后面怎么多出个117，请教各位帮我看一下代码怎么修改

Public Class Form2
    Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
        Dim f As String
        '设置打开的文本格式
        OpenFileDialog1.Filter = "Text Files(*.TXT)|*.TXT"
        If OpenFileDialog1.ShowDialog = DialogResult.OK Then
            f = (OpenFileDialog1.FileName)
            '下面是把文本里的度分秒符号替换，这个是中海达格式
            f = Replace(Trim(f), "°", ",")
            f = Replace(Trim(f), "′", ",")
            f = Replace(Trim(f), "″,", ",")
            Dim f1 As String()
            Dim f2 As Double, f3 As Double, f4 As Double
            Dim f5 As String
            Dim i As Integer, i1 As Integer
            For i = 0 To f.Length
                f1 = f.Split(",")
                f2 = Val(f1(0) + f1(1) / 60 + f1(2) / 3600)
                f3 = Val(f1(3) + f1(4) / 60 + f1(5) / 3600)
                f4 = Val(f1(6))
                f5 = f1(7)
                TextBox1.Text = f2
                'TextBox2.Text = f3
                DataGridView1.Rows.Add(f2, f3, f4, f5)
            Next

        End If