DataGridView.CellParsing DataGridView.CellParsing DataGridView.CellParsing DataGridView.CellParsing Event

定义

在单元格值已修改的情况下,当单元格退出编辑模式时发生。Occurs when a cell leaves edit mode if the cell value has been modified.

public:
 event System::Windows::Forms::DataGridViewCellParsingEventHandler ^ CellParsing;
public event System.Windows.Forms.DataGridViewCellParsingEventHandler CellParsing;
member this.CellParsing : System.Windows.Forms.DataGridViewCellParsingEventHandler 
Public Custom Event CellParsing As DataGridViewCellParsingEventHandler 

示例

下面的代码示例演示如何处理CellParsing事件。The following code example shows how to handle the CellParsing event. 它还演示如何使用DataGridViewCellParsingEventArgs类。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.
void dataGridView1_CellParsing( Object^ /*sender*/, DataGridViewCellParsingEventArgs^ e )
{
   if ( this->dataGridView1->Columns[ e->ColumnIndex ]->Name->Equals( "Release Date" ) )
   {
      if ( e != nullptr )
      {
         if ( e->Value != nullptr )
         {
            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 ( FormatException^ /*ex*/ ) 
            {
               // Set to false in case another CellParsing handler
               // wants to try to parse this DataGridViewCellParsingEventArgs instance.
               e->ParsingApplied = false;
            }
         }
      }
   }
}
// Handling CellParsing allows one to accept user input, then map it to a different
// internal representation.
private void dataGridView1_CellParsing(object sender, DataGridViewCellParsingEventArgs e)
{
    if (this.dataGridView1.Columns[e.ColumnIndex].Name == "Release Date")
    {
        if (e != null)
        {
            if (e.Value != null)
            {
                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 (FormatException)
                {
                    // Set to false in case another CellParsing handler
                    // wants to try to parse this DataGridViewCellParsingEventArgs instance.
                    e.ParsingApplied = false;
                }
            }
        }
    }
}
' 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

注解

默认情况下DataGridView控件将尝试将转换为实际的基础单元格值指定单元格的类型中的单元格中显示的一个用户指定值ValueType属性。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. 这种转换使用返回的单元格的单元格样式的格式设置属性InheritedStyle属性。This conversion uses the formatting properties of the cell style returned by the cell InheritedStyle property.

如果标准转换不满足你的需求,处理CellParsing事件,以提供自定义值转换为所需的类型。If the standard conversion does not meet your needs, handle the CellParsing event to provide custom value conversion to the required type.

用户可以进入编辑模式,使用指定的方法EditMode属性,来退出编辑模式下,在单元格中,提交任何更改,通过将移动到另一个单元或通过按 ENTER。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. 按 esc 键将恢复对值的任何更改之前已提交,和CellParsing事件将会发生。Pressing ESC will revert any changes to the value before it is committed, and the CellParsing event will not occur. CellParsing事件发生仅当单元格的值实际上已被修改,即使最终值是与原始值相同。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. 它也会发生时CommitEdit调用方法。It also occurs when the CommitEdit method is called.

当处理CellParsing事件,您可以将值转换自己也可以自定义默认转换。When you handle the CellParsing event, you can convert the value yourself or you can customize the default conversion. 例如,您可以将值转换自己使用的单元格ParseFormattedValue与所选的类型转换器方法。For example, you can convert the value yourself using the cell ParseFormattedValue method with type converters of your choosing. 或者,可以让默认类型转换器分析的值,但需要修改NullValueDataSourceNullValue,并FormatProvider返回的对象的属性DataGridViewCellParsingEventArgs.InheritedCellStyle属性,则使用该单元格初始化InheritedStyle属性。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.

如果您自己转换值替换的初始的格式化值ConvertEventArgs.Value属性中指定单元格的类型转换后的值与ValueType属性。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. 若要指示不做进一步分析是有必要,设置DataGridViewCellParsingEventArgs.ParsingApplied属性设置为trueTo indicate that no further parsing is necessary, set the DataGridViewCellParsingEventArgs.ParsingApplied property to true.

事件处理程序完成后,如果ConvertEventArgs.Valuenull或者不是正确的类型,或DataGridViewCellParsingEventArgs.ParsingApplied属性是false,则Value使用单元格分析ParseFormattedValue与默认类型转换器方法。When the event handler completes, if the ConvertEventArgs.Value is null 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. 此方法的默认实现将分析值使用NullValueDataSourceNullValue,和FormatProvider中传递的单元格样式属性。The default implementation of this method parses the value using the NullValue, DataSourceNullValue, and FormatProvider properties of the cell style passed in. 如果值不等于NullValue,此值分析使用FormatProvider中传递的属性和类型转换器。If the value is not equal to NullValue, the value is parsed using the FormatProvider property and the type converters passed in.

若要自定义单元格的值转换为便于显示格式化值,请处理CellFormatting事件。To customize the conversion of a cell value into a formatted value for display, handle the CellFormatting event.

有关如何处理事件的详细信息,请参阅处理和引发事件For more information about how to handle events, see Handling and Raising Events.

适用于

另请参阅