单击时显示闪烁的光标

Question

我正在为我的某个应用程序使用水印。 （空盒子里有文字的地方）。这一切都很完美，除了当你点击这个盒子时，在你开始输入之前没有闪烁的光标。这似乎很简单，但我不知道该怎么做。

这是我正在使用的课程

  Imports System.ComponentModel
Public Class Watermark
    Inherits TextBox

    'Declare A Few Variables
    Dim WaterText As String
    Dim WaterColor As Color
    Dim WaterFont As Font
    Dim WaterBrush As SolidBrush
    Dim WaterContainer As Panel

    Public Sub New()
        MyBase.New()
        StartProcess()
    End Sub

    Private Sub StartProcess()
        'Assign Values To the Variables
        WaterText = "Default Watermark"
        WaterColor = Color.Gray
        WaterFont = New Font(Me.Font, FontStyle.Italic)
        WaterBrush = New SolidBrush(WaterColor)

        CreateWatermark()

        AddHandler TextChanged, AddressOf ChangeText
        AddHandler FontChanged, AddressOf ChangeFont
    End Sub

    Private Sub CreateWatermark()
        WaterContainer = New Panel
        Me.Controls.Add(WaterContainer)
        AddHandler WaterContainer.Click, AddressOf Clicked
        AddHandler WaterContainer.Paint, AddressOf Painted
    End Sub

    Private Sub RemoveWatermark()
        Me.Controls.Remove(WaterContainer)
    End Sub

    Private Sub ChangeText(ByVal sender As Object, ByVal e As EventArgs)
        If Me.TextLength <= 0 Then
            CreateWatermark()
        ElseIf Me.TextLength > 0 Then
            RemoveWatermark()
        End If
    End Sub

    Private Sub ChangeFont(ByVal sender As Object, ByVal e As EventArgs)
        WaterFont = New Font(Me.Font, FontStyle.Italic)
    End Sub

    Private Sub Clicked(ByVal sender As Object, ByVal e As EventArgs)
        Me.Focus()
    End Sub

    Private Sub Painted(ByVal sender As Object, ByVal e As PaintEventArgs)
        WaterContainer.Location = New Point(2, 0)
        WaterContainer.Anchor = AnchorStyles.Left Or AnchorStyles.Right
        WaterContainer.Height = Me.Height
        WaterContainer.Width = Me.Width
        WaterBrush = New SolidBrush(WaterColor)

        Dim Graphic As Graphics = e.Graphics
        Graphic.DrawString(WaterText, WaterFont, WaterBrush, New PointF(-2.0!, 1.0!))
    End Sub

    Protected Overrides Sub OnInvalidated(ByVal e As System.Windows.Forms.InvalidateEventArgs)
        MyBase.OnInvalidated(e)
        WaterContainer.Invalidate()
    End Sub

    <Category("Watermark Attributes"), Description("Sets Watermark Text")> Public Property WatermarkText As String
        Get
            Return WaterText
        End Get
        Set(ByVal value As String)
            WaterText = value
            Me.Invalidate()
        End Set
    End Property

    <Category("Watermark Attributes"), Description("Sets Watermark Color")> Public Property WatermarkColor As Color
        Get
            Return WaterColor
        End Get
        Set(ByVal value As Color)
            WaterColor = value
            Me.Invalidate()
        End Set
    End Property
End Class