vb怎么使指定的区域加亮显示

vb如何使指定的区域加亮显示
请问vb中如何使文本框里指定的行加亮显示啊，谢谢各位了。

[解决办法]
用富文本框控件可以做到.
[解决办法]

VB code

Private Sub Form_Load()    '文本框MultiLine在属性设置为True    Text1.Text = "aaaaaaa" & vbCrLf & _                 "bbbbbbbb" & vbCrLf & _                 "ccccccccc" & vbCrLf & _                 "dddddddddd"    Dim iLine As Integer, iLS() As String    Dim i As Integer, iLen1 As Integer        iLine = 3 '高亮第几行        iLS = Split(Text1, vbCrLf)    If iLine <= UBound(iLS) + 1 Then       For i = 0 To iLine - 2           iLen1 = iLen1 + Len(iLS(i)) + 2       Next       Text1.SelStart = iLen1       Text1.SelLength = Len(iLS(i))    End If           End Sub