Change Cell Text based on another in Windows Form DataGridView using C# and VB.Net

Hi gokuldas,

Refer below sample.

Code

C#

private void Form1_Load(object sender, EventArgs e)
{
    DataGridViewTextBoxColumn txtAmount = new DataGridViewTextBoxColumn();
    txtAmount.HeaderText = "Amount";
    txtAmount.Name = "txtAmount";
    txtAmount.Width = 100;

    DataGridViewTextBoxColumn txtPercentage = new DataGridViewTextBoxColumn();
    txtPercentage.HeaderText = "Percentage";
    txtPercentage.Name = "txtPercentage";
    txtPercentage.Width = 100;

    dataGridView1.Columns.Insert(0, txtPercentage);
    dataGridView1.Columns.Insert(1, txtAmount);
    this.dataGridView1.CellValidating += new
    DataGridViewCellValidatingEventHandler(dataGridView1_CellValidating);
}

private void dataGridView1_CellValidating(object sender, DataGridViewCellValidatingEventArgs e)
{
    string headerText = dataGridView1.Columns[e.ColumnIndex].HeaderText;
    int percentage = Convert.ToInt16(e.FormattedValue);
    if (!headerText.Equals("Percentage")) return;
    dataGridView1[e.ColumnIndex + 1, e.RowIndex].Value = 0;
}

VB.Net

Private Sub Form1_Load(ByVal sender As Object, ByVal e As EventArgs)Handle Me.Load
        Dim txtAmount As DataGridViewTextBoxColumn = New DataGridViewTextBoxColumn()
        txtAmount.HeaderText = "Amount"
        txtAmount.Name = "txtAmount"
        txtAmount.Width = 100
        Dim txtPercentage As DataGridViewTextBoxColumn = New DataGridViewTextBoxColumn()
        txtPercentage.HeaderText = "Percentage"
        txtPercentage.Name = "txtPercentage"
        txtPercentage.Width = 100
        dataGridView1.Columns.Insert(0, txtPercentage)
        dataGridView1.Columns.Insert(1, txtAmount)
        Me.dataGridView1.CellValidating += New DataGridViewCellValidatingEventHandler(AddressOf dataGridView1_CellValidating)
    End Sub

    Private Sub dataGridView1_CellValidating(ByVal sender As Object, ByVal e As DataGridViewCellValidatingEventArgs)
        Dim headerText As String = dataGridView1.Columns(e.ColumnIndex).HeaderText
        Dim percentage As Integer = Convert.ToInt16(e.FormattedValue)
        If Not headerText.Equals("Percentage") Then Return
        dataGridView1(e.ColumnIndex + 1, e.RowIndex).Value = 0
    End Sub

Screenshot