Watermark TextBox in WinForms

Question

Can anyone point me to a good implementation of a basic Windows Forms TextBox that will initially show watermark text that disappears when the cursor enters it? I think I ca

Answer 1

I wrote a reusable custom control class for my project.
maybe it can help someone that need to implement multiple placeholder textboxes in his project. here is the C# and vb.net versions:

C#:

namespace reusebleplaceholdertextbox
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void Form1_Load(object sender, EventArgs e)
        {
            // implementation
            CustomPlaceHolderTextbox myCustomTxt = new CustomPlaceHolderTextbox(
                "Please Write Text Here...", Color.Gray, new Font("ARIAL", 11, FontStyle.Italic)
                , Color.Black, new Font("ARIAL", 11, FontStyle.Regular)
                );

            myCustomTxt.Multiline = true;
            myCustomTxt.Size = new Size(200, 50);
            myCustomTxt.Location = new Point(10, 10);
            this.Controls.Add(myCustomTxt);
        }
    }

    class CustomPlaceHolderTextbox : System.Windows.Forms.TextBox
    {
        public string PlaceholderText { get; private set; }
        public Color PlaceholderForeColor { get; private set; }
        public Font PlaceholderFont { get; private set; }

        public Color TextForeColor { get; private set; }
        public Font TextFont { get; private set; }

        public CustomPlaceHolderTextbox(string placeholdertext, Color placeholderforecolor,
            Font placeholderfont, Color textforecolor, Font textfont)
        {
            this.PlaceholderText = placeholdertext;
            this.PlaceholderFont = placeholderfont;
            this.PlaceholderForeColor = placeholderforecolor;
            this.PlaceholderFont = placeholderfont;
            this.TextForeColor = textforecolor;
            this.TextFont = textfont;
            if (!string.IsNullOrEmpty(this.PlaceholderText))
            {
                SetPlaceHolder(true);
                this.Update();
            }
        }

        private void SetPlaceHolder(bool addEvents)
        {
            if (addEvents)
            {  
                this.LostFocus += txt_lostfocus;
                this.Click += txt_click;
            }

            this.Text = PlaceholderText;
            this.ForeColor = PlaceholderForeColor;
            this.Font = PlaceholderFont;
        }

        private void txt_click(object sender, EventArgs e)
        {
            // IsNotFirstClickOnThis:
            // if there is no other control in the form
            // we will have a problem after the first load
            // because we dont other focusable control to move the focus to
            // and we dont want to remove the place holder
            // only on first time the place holder will be removed by click event
            RemovePlaceHolder();
            this.GotFocus += txt_focus;
            // no need for this event listener now
            this.Click -= txt_click;
        }

        private void RemovePlaceHolder()
        {
            this.Text = "";
            this.ForeColor = TextForeColor;
            this.Font = TextFont;
        }
        private void txt_lostfocus(object sender, EventArgs e)
        {
            if (string.IsNullOrEmpty(this.Text))
            {
                // set placeholder again
                SetPlaceHolder(false);
            }
        }

        private void txt_focus(object sender, EventArgs e)
        {
            if (this.Text == PlaceholderText)
            {
                // IsNotFirstClickOnThis:
                // if there is no other control in the form
                // we will have a problem after the first load
                // because we dont other focusable control to move the focus to
                // and we dont want to remove the place holder
                RemovePlaceHolder();
            }
        }
    }
}

VB.NET:

---

Namespace CustomControls

    Public Class PlaceHolderTextBox
        Inherits System.Windows.Forms.TextBox

        Public Property PlaceholderText As String
        Public Property PlaceholderForeColor As Color
        Public Property PlaceholderFont As Font
        Public Property TextForeColor As Color
        Public Property TextFont As Font

        Public Sub New(ByVal placeholdertext As String, ByVal placeholderforecolor As Color, ByVal placeholderfont As Font, ByVal txtboxbackcolor As Color, ByVal textforecolor As Color, ByVal textfont As Font)
            Me.PlaceholderText = placeholdertext
            Me.PlaceholderFont = placeholderfont
            Me.PlaceholderForeColor = placeholderforecolor
            Me.PlaceholderFont = placeholderfont
            Me.TextForeColor = textforecolor
            Me.TextFont = textfont
            Me.BackColor = txtboxbackcolor
            If Not String.IsNullOrEmpty(Me.PlaceholderText) Then
                SetPlaceHolder(True)
                Me.Update()
            End If
        End Sub

        Private Sub SetPlaceHolder(ByVal addEvents As Boolean)
            If addEvents Then
                AddHandler Me.LostFocus, AddressOf txt_lostfocus
                AddHandler Me.Click, AddressOf txt_click
            End If

            Me.Text = PlaceholderText
            Me.ForeColor = PlaceholderForeColor
            Me.Font = PlaceholderFont
        End Sub

        Private Sub txt_click(ByVal sender As Object, ByVal e As EventArgs)
            RemovePlaceHolder()
            AddHandler Me.GotFocus, AddressOf txt_focus
            RemoveHandler Me.Click, AddressOf txt_click
        End Sub

        Private Sub RemovePlaceHolder()
            Me.Text = ""
            Me.ForeColor = TextForeColor
            Me.Font = TextFont
        End Sub

        Private Sub txt_lostfocus(ByVal sender As Object, ByVal e As EventArgs)
            If String.IsNullOrEmpty(Me.Text) Then
                SetPlaceHolder(False)
            End If
        End Sub

        Private Sub txt_focus(ByVal sender As Object, ByVal e As EventArgs)
            If Me.Text = PlaceholderText Then
                RemovePlaceHolder()
            End If
        End Sub
    End Class

End Namespace