custom property for columns in datagridview

Question

Good morning ,

I have a custom-datagridview with 5 columns in which there is a need for the column number 3,4,5 to convert its value from 3200 to 3,200.00 automatically . Is there a property for the same . Another problem is i want to make sure that columns 3 , 4 ,5 can let the user type alphabets in them(besides numbers and decimal and comma character) but when he presses enter , nothing should happen untill he corrects the value . Can i create a property for this . I know that the relevant events might are cellendedit and datagridvieweditingcontrolshowing but i don't know how to use them accordingly . Please help

Answer 1

Hi @Rahul Kumar , Welcome to Microsoft Q&A,

First make sure your data is entered via binding. Your needs can be accomplished through CellFormatting and CellValidating. Since the input contains letters, I assume the input is a string. You first need to separate it into the numeric part and the letter part and deal with them separately.

For cellvaliding, when the requirements are not met, Use e.Cancel = true; to cancel the customer's operation.

using System.Collections.Generic;
using System.Windows.Forms;

namespace _10_30_x
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void dataGridView1_CellFormatting(object sender, DataGridViewCellFormattingEventArgs e)
        {
            if (e.RowIndex >= 0 && (e.ColumnIndex == 2 || e.ColumnIndex == 3 || e.ColumnIndex == 4))
            {
                string originalValue = e.Value as string;

                if (!string.IsNullOrEmpty(originalValue))
                {
                    string numericPart = string.Empty;
                    string nonNumericPart = string.Empty;

                    foreach (char c in originalValue)
                    {
                        if (char.IsDigit(c) || c == '.' || c == ',')
                        {
                            numericPart += c;
                        }
                        else
                        {
                            nonNumericPart += c;
                        }
                    }

                    if (!string.IsNullOrEmpty(numericPart))
                    {
                        if (decimal.TryParse(numericPart, out decimal parsedValue))
                        {
                            e.Value = parsedValue.ToString("N2") + nonNumericPart;
                            e.FormattingApplied = true;
                        }
                    }
                }
            }
        }

        private void dataGridView1_CellValidating(object sender, DataGridViewCellValidatingEventArgs e)
        {
            if (e.ColumnIndex == 2 || e.ColumnIndex == 3 || e.ColumnIndex == 4)
            {
                string value = e.FormattedValue.ToString();
                foreach (char c in value)
                {
                    if (!System.Text.RegularExpressions.Regex.IsMatch(value, "^[a-zA-Z0-9,.]*$"))
                    {
                        e.Cancel = true;
                        MessageBox.Show("Only numbers, letters and commas are allowed.");
                        break;
                    }
                }
            }
        }
        class goods
        {
            public string name { get; set; }
            public string count1 { get; set; }
            public string count2 { get; set; }
            public string count3 { get; set; }
            public string count4 { get; set; }
        }
        private void Form1_Load(object sender, System.EventArgs e)
        {
            List<goods> goods = new List<goods> { };
            goods.Add(new goods() { name = "apple", count1 = "1", count2 = "26666av", count3 = "3", count4 = "4" });
            goods.Add(new goods() { name = "banana", count1 = "1", count2 = "226663gg", count3 = "66663", count4 = "4" });

            goods.Add(new goods() { name = "orange", count1 = "1", count2 = "24", count3 = "35", count4 = "4" });
            dataGridView1.DataSource = goods;
        }
    }
}

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.