(datagridview)根据列值更新行的字体颜色

Question

我想询问一行如何根据列的值自动更新其字体的颜色dataGridView.

例如,一个表有4列:id, name, rentPayMent and check.

检查每一行是否有任何值check == 0 如果是,那么这行的字体为color = red Elsedo nothing

在运动中,我使用下面的代码,但它带来了错误

对象引用未设置为对象的实例,System.NullReferenceException未处理

private void dataGridView1_DataBindingComplete(object sender, DataGridViewBindingCompleteEventArgs e)
{
    foreach (DataGridViewRow row in dataGridView1.Rows)
    {
        if (row.Cells[3].Value.ToString() == "0") //**Object reference not set to an instance of an object**
        {
            row.DefaultCellStyle.BackColor = Color.Red;  //then change row color to red
        }
    }
}

谢谢大家,我已经得到了解决方案.

    private void dataGridView1_CellFormatting(object sender, DataGridViewCellFormattingEventArgs e)
    {
        if (dataGridView1.Rows[e.RowIndex].Cells[3].Value != null && !string.IsNullOrWhiteSpace(dataGridView1.Rows[e.RowIndex].Cells[3].Value.ToString()))
        {
            if (dataGridView1.Rows[e.RowIndex].Cells[3].Value.ToString().Trim() == "0")
                dataGridView1.Rows[e.RowIndex].DefaultCellStyle = new DataGridViewCellStyle { ForeColor = Color.Red };
        }
        else
        {
            dataGridView1.Rows[e.RowIndex].Cells[3].Style = dataGridView1.DefaultCellStyle;
        }

    }

Answer 1

private void dataGridView1_CellFormatting(object sender, DataGridViewCellFormattingEventArgs e)
{
    if (dataGridView1.Rows[e.RowIndex].Cells[e.ColumnIndex].Value != null && !string.IsNullOrWhiteSpace(dataGridView1.Rows[e.RowIndex].Cells[e.ColumnIndex].Value.ToString()))
    {
        dataGridView1.Rows[e.RowIndex].Cells[e.ColumnIndex].Style = new DataGridViewCellStyle { ForeColor = Color.Orange, BackColor = Color.Blue };
    }
    else
    {
        dataGridView1.Rows[e.RowIndex].Cells[e.ColumnIndex].Style = dataGridView1.DefaultCellStyle;
    }
}