Finding the sender for OnEnter event

Question

Below is the code snippet for my customdatagridview .

  protected override void OnEnter(EventArgs e)
        {
            // datagridview has data 
            if (this.RowCount > 0)
            {
                if (// what condition)
                {
                    this.CurrentCell = this.Rows[0].Cells[0]; // select the first cell in the first row
                }
                else // second textbox causes 
                {
                    this.CurrentCell = this[0, this.RowCount - 1]; // select the last row's first cell
                }
               // rest of stuff
            base.OnEnter(e);
        }

Now on the windows forms , besides the above customdatagridview , I have two textboxes(they are also custom textboxes) on my form . both of them on pressing enter are causing the onenter event of this customdatagridview to get triggered . The scenario is I want to check which textbox causes the datagridview to trigger its onenter event . But the real problem is i do not access to these textboxes in this customdatagridview.cs file .

Answer 1

Hi @rahul kumar , Welcome to Microsoft Q&A.

Updated：

You can use tabindex comparison to determine which textbox it is from.

The demo I gave in the question is just for show about the problem.

Define a public datagridview in customtextbox, and assign mydatagridview to it in the main form, so it can be accessed normally.

mydatagridview :

using System;
using System.Windows.Forms;

namespace _7_18_cc
{
    public partial class mydatagridview : DataGridView
    {
        public mydatagridview()
        {
            InitializeComponent();
            this.AllowUserToAddRows = false;
        }

        protected override void OnPaint(PaintEventArgs pe)
        {
            base.OnPaint(pe);
        }
        protected override void OnEnter(EventArgs e)
        {
            base.OnEnter(e);
        }
    }
}

customtextbox:

using System.Windows.Forms;
namespace _7_18_cc
{
    public partial class customtextbox: TextBox
    {
        public DataGridView tmpData;
        public customtextbox()
        {
            base.AutoSize = false;
            this.BorderStyle = BorderStyle.None;
            this.Font = new System.Drawing.Font("Microsoft Sans Serif", 9 F, System.Drawing.FontStyle.Bold, System.Drawing.GraphicsUnit.Point, 0);
            InitializeComponent();
        }
        protected override void OnKeyDown(KeyEventArgs e)
        {
            if((e.KeyCode == Keys.Enter || e.KeyCode == Keys.Down))
            {
                if(!string.IsNullOrEmpty(this.Text))
                {
                    e.Handled = true;
                    if(this.TabIndex < tmpData.TabIndex)
                    {
                        tmpData.Rows.Add();
                        tmpData.CurrentCell = tmpData.Rows[0].Cells[0];
                        tmpData.BeginEdit(true);
                    }
                }
                else if(tmpData.Rows.Count > 0 && this.TabIndex > tmpData.TabIndex)
                {
                    tmpData.CurrentCell = tmpData.Rows[tmpData.Rows.Count - 1].Cells[0];
                    tmpData.BeginEdit(true);
                }
                return;
            }
            base.OnKeyDown(e);
        }
        protected override void OnPaint(PaintEventArgs pe)
        {
            base.OnPaint(pe);
        }
    }
}

MainForm:

using System.Windows.Forms;

namespace _7_19_x
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
            customtextbox1.tmpData = mydatagridview1;
            customtextbox2.tmpData = mydatagridview1;
        }
    }
}

Best Regards,

Jiale

---

If the answer is the right solution, please click "Accept Answer" and kindly upvote it. If you have extra questions about this answer, please click "Comment". 

Note: Please follow the steps in our documentation to enable e-mail notifications if you want to receive the related email notification for this thread.