DataGridView: Change Edit Control size while editing

Question

in the DataGridView I want the cell size to expand according to the string length when I edit the cell. Excel does the same.

In the DataGridView, w

Answer 1

I mentioned in my other answer that I had two solutions, this one is the MeasureString solution (as opposed to the second datagridview solution)

any mention of textbox1-5.text e.t.c. has been commented it was just for debugging.

this, and the other solution, doesn't just resize the column you are editting in, it also resizes datagridview's width, and the form width, though you can easily comment that if you don't want that behaviour.

I should probably have used the 'uses' keyword for creating the graphics object, but anyhow.

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;

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

        private void dataGridView1_CellBeginEdit(object sender, DataGridViewCellCancelEventArgs e)
        {

            int origColumnWidth = dataGridView1.Columns[e.ColumnIndex].Width;

            dataGridView1.Columns[e.ColumnIndex].AutoSizeMode = DataGridViewAutoSizeColumnMode.None;

            dataGridView1.Columns[e.ColumnIndex].Width = origColumnWidth;

            if (dataGridView1.CurrentCell == null) dataGridView1.CurrentCell.Value = "";


        }

        private void dataGridView1_CellEndEdit(object sender, DataGridViewCellEventArgs e)
        {
            dataGridView1.Columns[e.ColumnIndex].AutoSizeMode = DataGridViewAutoSizeColumnMode.AllCells;
        }

        private void dataGridView1_EditingControlShowing(object sender, DataGridViewEditingControlShowingEventArgs e)
        {

            if (e.Control is TextBox)
            {
                var tbox = (e.Control as TextBox);

                // De-register the event FIRST so as to avoid multiple assignments (necessary to do this or the event
                // will be called +1 more time each time it's called).

                tbox.TextChanged -= TextBoxChanged;
                tbox.TextChanged += TextBoxChanged;

            }

        }

        private void TextBoxChanged(object sender, EventArgs e)
        {

            // try catch is helpful in a winforms program 'cos otherwise program might just stop.
            // http://stackoverflow.com/questions/1583351/silent-failures-in-c-seemingly-unhandled-exceptions-that-does-not-crash-the-pr

            try
            {
                int colindex = dataGridView1.CurrentCell.ColumnIndex;

                Graphics agraphics = this.CreateGraphics();

                SizeF headerTextSize = agraphics.MeasureString(dataGridView1.Columns[colindex].HeaderText, dataGridView1.EditingControl.Font);

                // sometimes it goes black and this link here says to use editing control http://stackoverflow.com/questions/3207777/datagridview-cell-turns-black-when-accessing-editedformattedvalue

                // string stredit=dataGridView1.CurrentCell.EditedFormattedValue.ToString();
                string stredit=myDataGridView.EditingControl.Text;
                SizeF curCellTextSize = agraphics.MeasureString(stredit, dataGridView1.EditingControl.Font);
                //SizeF curCellTextSize = agraphics.MeasureString(dataGridView1.CurrentCell.GetEditedFormattedValue.ToString(), dataGridView1.EditingControl.Font);
                int curCellTextSize_i = (int)Math.Round(curCellTextSize.Width, 0);

                int headerCellSize = dataGridView1.Columns[colindex].Width;

                textBox2.Text = headerTextSize.Width.ToString();
                textBox3.Text = headerCellSize.ToString();

                // find biggest existing one
                int maxcelltextincol = (int)Math.Round(headerTextSize.Width,0);
                // the max size, at least for the header, includes a bit of padding.. 
                maxcelltextincol += 20;
                int tempcelllength=0;
                for(int i=0; i maxcelltextincol) maxcelltextincol = tempcelllength;       
                }


            //    textBox2.Text = "PRE curCellTextSize_i=" + curCellTextSize_i + " " + "dgvw=" + dataGridView1.Columns[colindex].Width.ToString() + " max=" + maxcelltextincol.ToString() +  " prevstringlength=";

                string txtinwhatiamediting = stredit;

                SizeF sizelengthoftxtinwhatiamediting = agraphics.MeasureString(txtinwhatiamediting, dataGridView1.Font); //intermediate
                int lengthoftxtinwhatiamediting=(int)Math.Round(sizelengthoftxtinwhatiamediting.Width,0);

                //if(lengthoftxtinwhatiamediting>maxcelltextincol) 
                int amountovermax = lengthoftxtinwhatiamediting - maxcelltextincol;    


                int oldcolwidth = dataGridView1.Columns[colindex].Width;
                if (amountovermax < 0) { dataGridView1.Columns[colindex].Width = maxcelltextincol; return; }


                dataGridView1.Columns[colindex].Width = maxcelltextincol + amountovermax;
                int newcolwidth = dataGridView1.Columns[colindex].Width;
                   //dataGridView1.Width += (int)Math.Round((double)amountovermax,0);
                dataGridView1.Width += newcolwidth - oldcolwidth;
                this.Width += newcolwidth - oldcolwidth;
                //   textBox2.Text = "curCellTextSize_i=" + curCellTextSize_i + " " + "dgvw=" + dataGridView1.Columns[colindex].Width.ToString() + " max=" + maxcellincol.ToString();

                if (curCellTextSize_i > maxcelltextincol) maxcelltextincol = curCellTextSize_i;

                  // textBox5.Text= "POST curCellTextSize_i=" + curCellTextSize_i + " " + "dgvw=" + dataGridView1.Columns[colindex].Width.ToString() + " max=" + maxcelltextincol.ToString() + "prevstring=" + prevString + " prevstringlength=" + prevtextsize + " diff=" + diff;
                 //  textBox5.Text = "POST curCellTextSize_i=" + curCellTextSize_i + " " + "dgvw=" + dataGridView1.Columns[colindex].Width.ToString() + " max=" + maxcelltextincol.ToString() + " diff=" + amountovermax;


            }
            catch (Exception ee) { MessageBox.Show(ee.ToString()); }                                
        }

        private void Form1_Load(object sender, EventArgs e)
        {
            try
            {
                //dataGridView1.AllowUserToAddRows = false;
                dataGridView1.Font = new System.Drawing.Font("David", 30.25F, System.Drawing.FontStyle.Bold, System.Drawing.GraphicsUnit.Point, ((byte)(0)));
                dataGridView1.Rows.Add(1);

                dataGridView1.AutoSizeRowsMode = DataGridViewAutoSizeRowsMode.AllCells;
                dataGridView1.AutoSizeColumnsMode = DataGridViewAutoSizeColumnsMode.AllCells;                

                Graphics g = this.CreateGraphics(); // should be in a using.

                Font fontA = new System.Drawing.Font("David", 30.25F, System.Drawing.FontStyle.Bold, System.Drawing.GraphicsUnit.Point, ((byte)(0)));

                SizeF headerSize = g.MeasureString(dataGridView1.Columns[0].HeaderText, fontA);

                int totalcolwidth = dataGridView1.RowHeadersWidth + 40; // about 40+70
                //MessageBox.Show(totalcolwidth.ToString());
                for (int i = 0; i < dataGridView1.Columns.Count; i++)
                    totalcolwidth += dataGridView1.Columns[i].Width;

              //  MessageBox.Show(totalcolwidth.ToString());
              //  MessageBox.Show(dataGridView1.Width.ToString());
                int diff = totalcolwidth - dataGridView1.Width;
                dataGridView1.Width = totalcolwidth;
              //  MessageBox.Show(dataGridView1.Width.ToString());
                this.Width += diff;

            }
            catch (Exception exc)
            {
                MessageBox.Show("exception ");
                MessageBox.Show(exc.ToString());
            }
        }


    }
}