How to make a datagrid double column nullable

I have a DataGrid bound to a DataTable. Some of the column are of type double. As you know, double doesn't accept null value, and the column doesn't accept double? (or Nullable<double>) as its type. How can I make the column to accept null values?

Try

DataGridView1.CurrentCell.Value = DBNull.Value

How to make a datagrid double column nullable, I have always known a lot of people who have problems with the standard .NET 2.0 DataGridView and the nullable DateTime column (created with Oracle PL/​SQL column definition): RowCount = 5; foreach (DataGridViewRow row in this. Introduction. It's quite common to bind a WPF DataGrid to data using autogenerated columns. It's equally common to have bound properties of a nullable type (ie Nullable<int>) . However DataGrid does not provide the standard sorting behaviour for nullable types, the column header is not highlighted and clicking has no action.

((DataGridBoundColumn)e.Column).Binding.TargetNullValue = string.Empty;

Try setting DataGridAutoGeneratingColumnEventArgs as an event handler when the column is created, and doing the above. This will let your data columns accept empty values when of type double.

Nullable datetime column in .NET DataGrid with DateTimePicker , A little problem I ran into recently was to do with an object I was using to databind to. The obect contains two 'int? nullable types and as a result once you add a value into the field I was finding that any attempt to delete out  I'm writing an datagriview column to handle the user entering null values(in this case if a leave date is not set for a user it's stored as null and displayed as an N/A) I've almost got it working using a nullable datetimepicker but the grid doesn't pick up on the change to a null value, it just switches back to the old time value.

I solved it using a Converter associated with the binding that translates the "" or null to DBNull.value

//Converter to accept null values in Datagrid not String columns
class DatagridContentConverter : IValueConverter
{
    public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
    {
        return value;
    }

    public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
    {
        if (value == null || ((value.GetType() == typeof(String) && (String)value == "")))
        {
            return DBNull.Value;
        }
        else
        {
            return value;
        }
    }
}

WPF DataGrid – Binding with Nullable Types, The following code example first creates a new DataGridBoolColumn and adds it to the GridColumnStylesCollection of a First check for a null // table or data grid. if (this. To use two-state check boxes, set the AllowNull property to false . I got here looking for a solution to the same problem: constraining the input into cells on a DataGrid to be numeric. But the accepted answer did not work for me. The following did: For the DataGrid add an event handler for PreparingForCellEdit.

DataGridBoolColumn Class (System.Windows.Forms), The DataGridBoolcolumn displays a check box in the DataGrid for each row, Similarly, Nullvalue indicates the returned value when the bound data contains a null You set the Format property to the string "D", and it is output as "Saturday,  If you let me know, I'll write you a handler so that we can examine the value in your validating event, and if the date is not proper, we can examine the underlying datasource, and view the .OriginalValue of the column for the row, and if it was null, then we can simply reset that value to null.

Sams Teach Yourself .NET Windows Forms in 21 Days, Learn about Filtering support in Syncfusion WPF DataGrid (SfDataGrid) control and more details. SfDataGrid filter UI comprises of two different UIs. Checkbox Filter UI - Provides FilterPopupStyle is set as null for OrderID column. So both  Changing the data structure of a column in SQL Server from NULL to NOT NULL, thereby disallowing non-null values in that column, is generally performed using the relatively simple ALTER TABLE syntax to appropriately change the column in question.

Filtering in WPF DataGrid control, how do you manage a datagridview that has null values? for for example i have a datagridview with a column FirstName, MiddleName, LastName etc. "​this causes two bindings in the collection to bind to the same property  If you look at the code generated by the DataSet generator for a DateTime column you'll notice that it simply casts the result of. the DataRow's indexer to DateTime and throws an exception if the value cannot be cast. Nullable in this case is not very useful. since the returned value will never be null!

Comments
  • The type of the column will be System.Double but it accepts null values anyway, you have to pass them as DBNull.Value. If the table was loaded with a DataAdapter you don't need to do anything.
  • It is a Two-way bind. So the user may delete a cell. Then the empty cell will become red and other cells cannot be selected.
  • the cell value is not updated yet for me to make it DBNull
  • Every column has property ConvertEmptyStringToNull="true". It converts not filled values to null
  • Beautiful. Goes well with if (e.PropertyType.IsGenericType && e.PropertyType.GetGenericTypeDefinition() == typeof(Nullable<>))