how to change the position of the icon in the textbox class with VB.NET

I'm trying to change the position of the icon in the textbox class with VB.NET

Public Class SearchTextBox
        Inherits TextBox
        Private Const EM_SETMARGINS As Integer = &Hd3
        <System.Runtime.InteropServices.DllImport("user32.dll")>
        Private Shared Function SendMessage(ByVal hWnd As IntPtr, ByVal msg As Integer, ByVal wp As IntPtr, ByVal lp As IntPtr) As IntPtr
        End Function

        Private searchPictureBox As PictureBox

        Private cancelSearchButton As Button

        Public Sub New()
            cancelSearchButton = New Button()
            cancelSearchButton.Anchor = AnchorStyles.Top Or AnchorStyles.Right
            cancelSearchButton.Size = New Size(16, 16)
            cancelSearchButton.TabIndex = 0
            cancelSearchButton.TabStop = False
            cancelSearchButton.FlatStyle = FlatStyle.Flat
            cancelSearchButton.FlatAppearance.BorderSize = 0
            cancelSearchButton.Text = ""
            cancelSearchButton.Cursor = Cursors.Arrow

            Controls.Add(cancelSearchButton)

            AddHandler cancelSearchButton.Click, Sub()
                Text = ""
                Focus()
            End Sub

            searchPictureBox = New PictureBox()
            searchPictureBox.Anchor = AnchorStyles.Top Or AnchorStyles.Right
            searchPictureBox.Size = New Size(16, 16)
            searchPictureBox.TabIndex = 0
            searchPictureBox.TabStop = False
            Controls.Add(searchPictureBox)

            ' Send EM_SETMARGINS to prevent text from disappearing underneath the button
            SendMessage(Handle, EM_SETMARGINS, New IntPtr(2), New IntPtr(16 << 16))

            UpdateControlsVisibility()
        End Sub

        Protected Overrides Sub OnTextChanged(ByVal e As EventArgs)
            MyBase.OnTextChanged(e)
            UpdateControlsVisibility()
        End Sub

        Private Sub UpdateControlsVisibility()
            If String.IsNullOrEmpty(Text) Then
                cancelSearchButton.Visible = False
                searchPictureBox.Visible = True
            Else
                cancelSearchButton.Visible = True
                searchPictureBox.Visible = False
            End If
        End Sub

        <Browsable(True)>
        Public Property SearchImage As Image
            Set(ByVal value As Image)
                searchPictureBox.Image = value
                searchPictureBox.Left = Width - searchPictureBox.Size.Width - 4
                searchPictureBox.Top = Height - searchPictureBox.Size.Height - 4
            End Set

            Get
                Return searchPictureBox.Image
            End Get
        End Property

        <Browsable(True)>
        Public Property CancelSearchImage As Image
            Set(ByVal value As Image)
                cancelSearchButton.Image = value
                cancelSearchButton.Left = Width - searchPictureBox.Size.Width - 4
                cancelSearchButton.Top = Height - searchPictureBox.Size.Height - 4
            End Set

            Get
                Return cancelSearchButton.Image
            End Get
        End Property
    End Class

result from code

Desired Result

Solution

Here is your code with the expected result.

Edit : I added an overide for OnSizeChanged in order to correctly position the icons when the size of the textbox changes

Imports System.ComponentModel

Public Class SearchTextBox
    Inherits TextBox

    Private Const EM_SETMARGINS As Integer = &HD3

    <System.Runtime.InteropServices.DllImport("user32.dll")>
    Private Shared Function SendMessage(ByVal hWnd As IntPtr, ByVal msg As Integer, ByVal wp As IntPtr, ByVal lp As IntPtr) As IntPtr
    End Function

    Private ReadOnly _IconPictureBox As PictureBox

    Private _searchImage As Image

    Private _cancelSearchImage As Image


    Public Sub New()
        _IconPictureBox = New PictureBox With {
            .Anchor = AnchorStyles.Top Or AnchorStyles.Right,
            .Size = New Size(Height - (Margin.Vertical + 2), Height - (Margin.Vertical + 2)),
            .Top = Margin.Top,
            .Left = Margin.Left,
            .TabIndex = 0,
            .TabStop = False,
            .SizeMode = PictureBoxSizeMode.StretchImage
        }
        AddHandler _IconPictureBox.Click, Sub()
                                              Text = ""
                                              Focus()
                                          End Sub
        Controls.Add(_IconPictureBox)

        ' Send EM_SETMARGINS to prevent text from disappearing underneath the button
        SendMessage(Handle, EM_SETMARGINS, New IntPtr(2), New IntPtr(16 << 16))
    End Sub

    Protected Overrides Sub OnTextChanged(ByVal e As EventArgs)
        MyBase.OnTextChanged(e)
        UpdateIcon()
    End Sub

    Protected Overrides Sub OnSizeChanged(ByVal e As EventArgs)
        MyBase.OnSizeChanged(e)
        UpdateIcon()
    End Sub

    Private Sub UpdateIcon()
        If String.IsNullOrEmpty(Text) Then
            _IconPictureBox.Image = _searchImage
            _IconPictureBox.Left = Margin.Left
        Else
            _IconPictureBox.Image = _cancelSearchImage
            _IconPictureBox.Cursor = Cursors.Arrow
            _IconPictureBox.Left = Width - _IconPictureBox.Size.Width - Margin.Horizontal
        End If
    End Sub

    <Browsable(True)>
    Public Property SearchImage As Image
        Set(value As Image)
            _searchImage = value
            UpdateIcon()
        End Set

        Get
            Return _searchImage
        End Get
    End Property

    <Browsable(True)>
    Public Property CancelSearchImage As Image
        Set(value As Image)
            _cancelSearchImage = value
            UpdateIcon()
        End Set

        Get
            Return _cancelSearchImage
        End Get
    End Property
End Class

Here is the result :

When the textbox is empty :

When there is content :

If necessary, here are the images I used :