Align Text in Combobox

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I want to align my text in combo box so that it will show in the center of combobox tell me how to do this also you can see there is a default border around a combo box when it is in focus how can i remove that border also Kindly solve my two problems Thanks

6 Answers

The post is a bit old but it may be still worth to say:

both requirements are possible for Windows Forms ComboBox:

  • Text align center (text area and the dropdown)
    • For the text area, find the Edit control and set the ES_CENTER style for the control.
    • For the dropdown items or the selected item in drop-down mode, to align text to center, just make the control owner-drawn and draw the text at center.
  • Get rid of focus rectangle
    • Make the control owner-drawn and just don't draw focus rectangle.

Example

using System;
using System.Runtime.InteropServices;
using System.Windows.Forms;
public class MyComboBox : ComboBox
{
    public MyComboBox()
    {
        DrawMode = DrawMode.OwnerDrawFixed;
    }

    [DllImport("user32.dll")]
    static extern int GetWindowLong(IntPtr hWnd, int nIndex);
    [DllImport("user32.dll")]
    static extern int SetWindowLong(IntPtr hWnd, int nIndex, int dwNewLong);
    const int GWL_STYLE = -16;
    const int ES_LEFT = 0x0000;
    const int ES_CENTER = 0x0001;
    const int ES_RIGHT = 0x0002;
    [StructLayout(LayoutKind.Sequential)]
    public struct RECT
    {
        public int Left;
        public int Top;
        public int Right;
        public int Bottom;
        public int Width { get { return Right - Left; } }
        public int Height { get { return Bottom - Top; } }
    }
    [DllImport("user32.dll")]
    public static extern bool GetComboBoxInfo(IntPtr hWnd, ref COMBOBOXINFO pcbi);

    [StructLayout(LayoutKind.Sequential)]
    public struct COMBOBOXINFO
    {
        public int cbSize;
        public RECT rcItem;
        public RECT rcButton;
        public int stateButton;
        public IntPtr hwndCombo;
        public IntPtr hwndEdit;
        public IntPtr hwndList;
    }
    protected override void OnHandleCreated(EventArgs e)
    {
        base.OnHandleCreated(e);
        SetupEdit();
    }
    private int buttonWidth = SystemInformation.HorizontalScrollBarArrowWidth;
    private void SetupEdit()
    {
        var info = new COMBOBOXINFO();
        info.cbSize = Marshal.SizeOf(info);
        GetComboBoxInfo(this.Handle, ref info);
        var style = GetWindowLong(info.hwndEdit, GWL_STYLE);
        style |= 1;
        SetWindowLong(info.hwndEdit, GWL_STYLE, style);
    }
    protected override void OnDrawItem(DrawItemEventArgs e)
    {
        base.OnDrawItem(e);
        e.DrawBackground();
        var txt = "";
        if (e.Index >= 0)
            txt = GetItemText(Items[e.Index]);
        TextRenderer.DrawText(e.Graphics, txt, Font, e.Bounds,
            ForeColor, TextFormatFlags.Left | TextFormatFlags.HorizontalCenter);
    }
}
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