リファレンス
StdFuncクラス FileReadLinesメソッド
テキストファイルから1行ごとの文字列配列として読み込みます。
成功した場合は文字列配列、失敗した場合はNothingが返ります。
使用法
Dim instance As StdFunc = New StdFunc()
Dim filePathName As String	'ファイルのフルパス
Dim returnValue As String()	'成功:文字列配列  失敗:Nothing

returnValue = instance.FileReadLines(filePathName)	'エンコード指定なしの場合はUTF-8として読込

Dim instance As StdFunc = New StdFunc()
Dim filePathName As String	'ファイルのフルパス
Dim encodeStr As String		'エンコードを表す文字列　"utf8" "shift_jis" "iso-2022-jp" "euc-jp"
Dim returnValue As String()	'成功:文字列配列  失敗:Nothing

returnValue = instance.FileReadLines(filePathName, encodeStr)

Dim instance As StdFunc = New StdFunc()
Dim filePathName As String	'ファイルのフルパス
Dim encode As System.Text.Encoding	'エンコード
Dim returnValue As String()	'成功:文字列配列  失敗:Nothing

returnValue = instance.FileReadLines(filePathName, encode)
使用例
'StdFuncクラス FileReadLinesメソッド

Imports System
Imports System.Windows.Forms
Imports Microsoft.VisualBasic

Public Class AddIn

	Private stdf As StdFunc

	Public Sub New()
		stdf = New StdFunc()
	End Sub

	Public Sub AddIn_Start()
		Dim fname As String = "D:\tmp\input.txt"
		Dim ary As String() = stdf.FileReadLines(fname)
		If ary Is Nothing Then
			MessageBox.Show("読み込みに失敗しました")
		Else
			Dim result As String = ""
			Dim num As Integer = 1
			For Each s As String In ary
				result &= num.ToString & " : " & s & ControlChars.CrLf
				num += 1
			Next
			MessageBox.Show(result)
		End If
	End Sub

End Class

'StdFuncクラス FileReadLinesメソッド

Imports System
Imports System.Windows.Forms
Imports Microsoft.VisualBasic

Public Class AddIn

	Private stdf As StdFunc

	Public Sub New()
		stdf = New StdFunc()
	End Sub

	Public Sub AddIn_Start()
		Dim fname As String = "D:\tmp\input.txt"
		Dim ary As String() = stdf.FileReadLines(fname, "euc-jp")
		If ary Is Nothing Then
			MessageBox.Show("読み込みに失敗しました")
		Else
			Dim result As String = ""
			Dim num As Integer = 1
			For Each s As String In ary
				result &= num.ToString & " : " & s & ControlChars.CrLf
				num += 1
			Next
			MessageBox.Show(result)
		End If
	End Sub

End Class

'StdFuncクラス FileReadLinesメソッド

Imports System
Imports System.Windows.Forms
Imports Microsoft.VisualBasic

Public Class AddIn

	Private stdf As StdFunc

	Public Sub New()
		stdf = New StdFunc()
	End Sub

	Public Sub AddIn_Start()
		Dim fname As String = "D:\tmp\input.txt"
		Dim ary As String() _
			= stdf.FileReadLines(fname, System.Text.Encoding.GetEncoding(932))
		If ary Is Nothing Then
			MessageBox.Show("読み込みに失敗しました")
		Else
			Dim result As String = ""
			Dim num As Integer = 1
			For Each s As String In ary
				result &= num.ToString & " : " & s & ControlChars.CrLf
				num += 1
			Next
			MessageBox.Show(result)
		End If
	End Sub

End Class