Something like this:
private void dataGridView1_CellContentClick_1(object sender, DataGridViewCellEventArgs e)
{
string str = dataGridView1.Rows[e.RowIndex].Cells[0].Value.ToString();
MessageBox.Show("You Have Selected " + str);
}
private void dataGridView1_CellValueChanged(object sender, DataGridViewCellEventArgs e)
{
if (this.dataGridView1.Columns[e.ColumnIndex].Name == "MyColumn")
{
string MyValue = this.dataGridView1.Rows[e.RowIndex].Cells[e.ColumnIndex].Value.ToString();
}
}