如何在数据网格视图窗口窗体中计算第 3 列中的第 1 列和第 2 列

Question

I want the subtraction of column 1 and column 2 in column 3 for a data grid view in windows form using C#. As of my knowledge we need to give cell content click event

//how to specify click only for column3
private void dataGridView2_CellContentClick(object sender, DataGridViewCellEventArgs e) {
  //here i need to give like column3 = column2 - column1 

}

Answer 1

I give here a code example demonstrating the use of a calculated column in a DataTable. This may be sufficient for your purposes.

public partial class Form1 : Form
{
    DataTable dt;
    public Form1()
    {
        InitializeComponent();
        dt = new DataTable();
        dt.Columns.Add(new DataColumn("col1", typeof(int)));
        dt.Columns.Add(new DataColumn("col2", typeof(int)));
        dt.Columns.Add(new DataColumn("col3", typeof(int), "col2 - col1"));
        var newRow = dt.NewRow();
        newRow[0] = 5;
        newRow[1] = 7;
        dt.Rows.Add(newRow);
        newRow = dt.NewRow();
        newRow[0] = 12;
        newRow[1] = 19;
        dt.Rows.Add(newRow);
        dataGridView1.AutoGenerateColumns = true;
        dataGridView1.DataSource = dt;
    }

    private void button1_Click(object sender, EventArgs e)
    {
        dt.Rows[0][0] = 10;
    }
}

The button click is deliberately crude, but I hope it is sufficient to demonstrate that if one field in the calculation alters, the calculation is refreshed immediately.