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这几年都在web项目上工作和学习，windows的项目也只是windows服务，界面上的学习少了。这几天看了看DataGridView，跟.net1.1的差别还是很大。实现自定义单元格编辑类的方式也不同了。主要是通过实现自己的DataGridViewColumn

微软有一篇文章

如何：在 Windows 窗体 DataGridView 单元格中承载控件

主要几步：

1。创建自己的DataGridViewColumn，重写

public override  DataGridViewCell CellTemplate
{
       get ;  
       set ;
}

2.创建自己的DataGridViewCell，用作上面的类返回的DataGridViewCell。重写

public override  Type EditType
{
     get  ;
}

public override  Type ValueType
{
     get ;
}

3.创建自己的EditType，该类需要实现System.Windows.Forms.IDataGridViewEditingControl接口

class  DataGridViewDecimalTextBoxEditingControl : TextBox, IDataGridViewEditingControl
{
// …一般让EditingControl继承自现有的控件或自己编写的windows自定义控件。
}

以下是一个完整的例子

public class  DataGridViewMoneyTextBoxColumn : DataGridViewTextBoxColumn
    {
         public  DataGridViewMoneyTextBoxColumn()
        {
             this .CellTemplate  = new  DataGridViewMoneyCell();           
        }
         public override  DataGridViewCell CellTemplate
        {
             get { return base .CellTemplate;
            }
             set {
                DataGridViewMoneyCell cell =  value  as  DataGridViewMoneyCell;
                 if  (value  != null &&  cell  == null )
                {
                     throw new  InvalidCastException( " Value provided for CellTemplate must be of type TEditNumDataGridViewCell or derive from it. " );
                }
                 base .CellTemplate  =  value;
            }            
        }
    }

     public class  DataGridViewMoneyCell : DataGridViewTextBoxCell
    {
         public  DataGridViewMoneyCell()
        {
            
        }
         int  decimalLength;

         private static  Type defaultEditType  = typeof (MoneyTextBoxDataGridViewEditingControl);
         private static  Type defaultValueType  = typeof (System.Decimal);

         public int  DecimalLength
        {
             get  {  return  decimalLength; }
             set  { decimalLength  =  value; }
        }

         public override  Type EditType
        {
             get  {  return  defaultEditType; }
        }

         public override  Type ValueType
        {
             get {
                Type valueType = base .ValueType;
                 if  (valueType  != null )
                {
                     return  valueType;
                }
                 return  defaultValueType;
            }
        }
   }
     public class  MoneyTextBoxDataGridViewEditingControl : TextBox, IDataGridViewEditingControl
    {
         private  DataGridView dataGridView;   //  grid owning this editing control
private bool  valueChanged;   //  editing control's value has changed or not
private int  rowIndex;   //   row index in which the editing control resides
#region  IDataGridViewEditingControl 成员 public void  ApplyCellStyleToEditingControl(DataGridViewCellStyle dataGridViewCellStyle)
        {
             this .Font  =  dataGridViewCellStyle.Font;
             if  (dataGridViewCellStyle.BackColor.A  < 255 )
            {
                 //  The NumericUpDown control does not support transparent back colors
Color opaqueBackColor =  Color.FromArgb( 255 , dataGridViewCellStyle.BackColor);
                 this .BackColor  =  opaqueBackColor;
                 this .dataGridView.EditingPanel.BackColor  =  opaqueBackColor;
            }
             else { this .BackColor  =  dataGridViewCellStyle.BackColor;
            }
             this .ForeColor  =  dataGridViewCellStyle.ForeColor;
        }

         public  DataGridView EditingControlDataGridView
        {
             get { return this .dataGridView; 
            }
             set { this .dataGridView  =  value;
            }
        }

         public object  EditingControlFormattedValue
        {
             get { return  GetEditingControlFormattedValue(DataGridViewDataErrorContexts.Formatting);
            }
             set { this .Text  =  ( string )value;
            }
        }

         public int  EditingControlRowIndex
        {
             get { return this .rowIndex;
            }
             set { this .rowIndex  =  value;
            }
        }

         public bool  EditingControlValueChanged
        {
             get  {  return this .valueChanged; }
             set  {  this .valueChanged  =  value; }
        }

         public bool  EditingControlWantsInputKey(Keys keyData,  bool  dataGridViewWantsInputKey)
        {
             switch  (keyData  &  Keys.KeyCode)
            {
                 case  Keys.Right:
                 case  Keys.Left:
                 case  Keys.Down:
                 case  Keys.Up:
                 case  Keys.Home:
                 case  Keys.End:
                 case  Keys.Delete:
                     return true ;
            }
             return ! dataGridViewWantsInputKey;
        }

         public  Cursor EditingPanelCursor
        {
             get  {  return  Cursors.Default; }
        }

         public object  GetEditingControlFormattedValue(DataGridViewDataErrorContexts context)
        {
             return this .Text;
        }

         public void  PrepareEditingControlForEdit( bool  selectAll)
        {
             if  (selectAll)
            {
                 this .SelectAll();
            }
             else { this .SelectionStart  = this .Text.Length;
            }
        }

         public bool  RepositionEditingControlOnValueChange
        {
             get  {  return false ; }
        }

         #endregion }

生成项目，如果是控件类库，引用到你的windows程序里，你就能从DataGridView编辑列里找到我们定义的DataGridViewColumn：DataGridViewTextBoxColumn

直白的说，就是第一步定义类把第二步的Cell类暴露给DataGridView，第二步的Cell类把我自己希望的编辑的控件暴露给DataGridView，当Cell被选中并处于编辑状态时，我们定义的控件就会被创建并显示给用户。