编写DataGridView自定义列编辑器(自定义单元格编辑类）

转自生命体验博客

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。