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DataGridView.CellParsing Event

Occurs when a cell leaves edit mode if the cell value has been modified.

Namespace:  System.Windows.Forms
Assembly:  System.Windows.Forms (in System.Windows.Forms.dll)

'Declaration
Public Event CellParsing As DataGridViewCellParsingEventHandler

By default, the DataGridView control will attempt to convert a user-specified value displayed in a cell to an actual underlying cell value in the type specified by the cell ValueType property. This conversion uses the formatting properties of the cell style returned by the cell InheritedStyle property.

If the standard conversion does not meet your needs, handle the CellParsing event to provide custom value conversion to the required type.

Users can enter edit mode using the method specified by the EditMode property, and can leave edit mode, committing any changes to a cell, by moving to another cell or by pressing ENTER. Pressing ESC will revert any changes to the value before it is committed, and the CellParsing event will not occur. The CellParsing event occurs only if the cell value has actually been modified, even if the final value is the same as the original value. It also occurs when the CommitEdit method is called.

When you handle the CellParsing event, you can convert the value yourself or you can customize the default conversion. For example, you can convert the value yourself using the cell ParseFormattedValue method with type converters of your choosing. Alternatively, you can let the default type converters parse the value, but modify the NullValue, DataSourceNullValue, and FormatProvider properties of the object returned by the DataGridViewCellParsingEventArgs.InheritedCellStyle property, which is initialized using the cell InheritedStyle property.

When you convert the value yourself, replace the initial, formatted value of the ConvertEventArgs.Value property with the converted value in the type specified by the cell ValueType property. To indicate that no further parsing is necessary, set the DataGridViewCellParsingEventArgs.ParsingApplied property to true.

When the event handler completes, if the ConvertEventArgs.Value is Nothing or is not of the correct type, or the DataGridViewCellParsingEventArgs.ParsingApplied property is false, the Value is parsed using the cell ParseFormattedValue method with default type converters. The default implementation of this method parses the value using the NullValue, DataSourceNullValue, and FormatProvider properties of the cell style passed in. If the value is not equal to NullValue, the value is parsed using the FormatProvider property and the type converters passed in.

To customize the conversion of a cell value into a formatted value for display, handle the CellFormatting event.

For more information about handling events, see Consuming Events.

The following code example shows how to handle the CellParsing event. It also shows how to use the DataGridViewCellParsingEventArgs class.

' Handling CellParsing allows one to accept user input, then map it to a different 
' internal representation. 
Private Sub dataGridView1_CellParsing(ByVal sender As Object, _
    ByVal e As DataGridViewCellParsingEventArgs) _
    Handles dataGridView1.CellParsing

    If Me.dataGridView1.Columns(e.ColumnIndex).Name = _
        "Release Date" Then 
        If e IsNot Nothing Then 
            If e.Value IsNot Nothing Then 
                Try 
                    ' Map what the user typed into UTC.
                    e.Value = _
                    DateTime.Parse(e.Value.ToString()).ToUniversalTime()
                    ' Set the ParsingApplied property to  
                    ' Show the event is handled.
                    e.ParsingApplied = True 

                Catch ex As FormatException
                    ' Set to false in case another CellParsing handler 
                    ' wants to try to parse this DataGridViewCellParsingEventArgs instance.
                    e.ParsingApplied = False 
                End Try 
            End If 
        End If 
    End If 
End Sub

.NET Framework

Supported in: 4.6, 4.5, 4, 3.5, 3.0, 2.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

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