Read Only Columns & Rows in a DataGridView

Question

I have a datagridview in a WinForms application and I want all columns bar one to be locked to editing. This I was able to achieve with the following code:

foreach (DataGridViewColumn col in myGrid.Columns)
{
    if (col.Name == "LockedColumn")
    {
        col.ReadOnly = false;
    }
    else
    {
        col.ReadOnly = true;
    }
}  

However, I also need a conditional lock on this column, dependent on the values elsewhere in each row. I tried the following code:

foreach (DataGridViewRow row in myGrid.Rows)
{
    if ((bool)row.Cells["ConditionalColumn"].Value == false)
    {
        row.ReadOnly = false;
    }
    else
    {
        row.ReadOnly = true;
    }
}     

However this locks the whole grid which is not what I want. What I'm after may be clearer with a table example.

ColA ColB ColC

row1 true value1

row2 false value2

row3 true value3

I want Columns A & B locked (read only) in their entirety, and the default for Col C to allow editing, except where the value in Column B is false. Hence in the above example only value1 and value3 would be editable.

However I can't seem to achieve this, because as stated above, if I loop through the rows with a condition that sets readonly to false, everything is locked.

Answer 1

The code you have shown should not compile and also isn't correctly examining the values within boolean cells in a DataGridView .

If you change your code to look at rows to something like the code below then you should be able to set individual rows to read only based on the column:

foreach (DataGridViewRow row in myGrid.Rows)
{
    if (row.Cells["ConditionalColumn"].Value == null || (bool)row.Cells["ConditionalColumn"].Value == false)
    {
        row.ReadOnly = false;
    }
    else
    {
        row.ReadOnly = true;
    }
}

Answer 2

It was the following line that was the issue

row.ReadOnly = false;

When changed to

row.Cells["colName"].ReadOnly = false;

it works as intended