Hi All,

I know c# has limitations on assigning null values to datetime and integer value types. But is there any trick I can utilize. I'm converting my appl. from another dec. tool wher I have no null issue, to c#. What I want to do is ; I populate my datagrdiview,
I do not want the same info to repeat itself on the second and following rows just for appearance purposes (like same nama/lastname not to appear after the first row, no problem with strings though). So I try to assign null values to the repeating info cells (string,int,date). How do I overcome int and datetime cells nulling limitations.

Thanks in advance
snakay

Value types can not become null.
But C# has what is called nullable types.
You define and use them like this :

bool? MyNullableBool;
            double? MyNullableDouble = 0.0;
            MyNullableBool = null;
            MyNullableDouble = null;

I see what you do but my problem is with the datagridview cell which is already populated with int or datetime data, and now I want to nullify them as follows;

// below is a string--no problem
r.Cells["colName"].Value = null;

// below is a datetime.I don't want to do this
r.Cells["colMyDate"].Value = DateTime.MinValue;

// below is an int.
r.Cells["colMyint"].Value =null;

I know I can't do what I did for int and datetime. But what can I do to clear those cells of grid so that you don't see any data there

You cannot assign null values like that to the grid but what you can do is use DBNull.Value . Here is a snippet where I am populating a grid and I check for nulls. If it is null then I use a DBNull in the grid:

dtRow[i1] = (gridRow.Cells[i1].Value == null ? DBNull.Value : gridRow.Cells[i1].Value);

thanks sknake,

it solves the problem

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