在DataGrid中简单使用下拉列表框

作者：Tushar Ameta

翻译：秋枫

在DataGrid中使用下拉列表问题。这篇文章讲了如何在 System.Windows.Forms.DataGrid中切入使用ComboBox控件。不过原文不全，无法调试，在这里为了说清楚点，对原文作了一些修改，整篇文章主要包括三方面的内容。

1． 在DataGrid中加入ComboBox列；

2． 把在DataGrid中的修改保存到对应的网格；

3． 设置DataGrid中网格的焦点。



下面是整个源代码，一些功能可以看注释。

using System;

using System.Drawing;

using System.Collections;

using System.ComponentModel;

using System.Windows.Forms;

using System.Data;



namespace DataGridTest

{

public class Form1 : System.Windows.Forms.Form

{

private System.Windows.Forms.DataGrid dgdFunctionArea;

private DataTable dtblFunctionalArea;

private System.Windows.Forms.Button buttonFocus;

private System.ComponentModel.Container components = null;



public Form1()

{

InitializeComponent();

PopulateGrid();

}



protected override void Dispose( bool disposing )

{

if( disposing )

{

if (components != null)

{

components.Dispose();

}

}

base.Dispose( disposing );

}



#region Windows 窗体设计器生成的代码

private void InitializeComponent()

{

this.dgdFunctionArea = new System.Windows.Forms.DataGrid();

this.buttonFocus = new System.Windows.Forms.Button();

((System.ComponentModel.ISupportInitialize)(this.dgdFunctionArea)).BeginInit();

this.SuspendLayout();

//

// dgdFunctionArea

//

this.dgdFunctionArea.DataMember = "";

this.dgdFunctionArea.HeaderForeColor = System.Drawing.SystemColors.ControlText;

this.dgdFunctionArea.Location = new System.Drawing.Point(4, 8);

this.dgdFunctionArea.Name = "dgdFunctionArea";

this.dgdFunctionArea.Size = new System.Drawing.Size(316, 168);

this.dgdFunctionArea.TabIndex = 0;

//

// buttonFocus

//

this.buttonFocus.Location = new System.Drawing.Point(232, 188);

this.buttonFocus.Name = "buttonFocus";

this.buttonFocus.Size = new System.Drawing.Size(84, 23);

this.buttonFocus.TabIndex = 1;

this.buttonFocus.Text = "获取焦点";

this.buttonFocus.Click += new System.EventHandler(this.buttonFocus_Click);

//

// Form1

//

this.AutoScaleBaseSize = new System.Drawing.Size(6, 14);

this.ClientSize = new System.Drawing.Size(332, 217);

this.Controls.Add(this.buttonFocus);

this.Controls.Add(this.dgdFunctionArea);

this.Name = "Form1";

this.Text = "Form1";

((System.ComponentModel.ISupportInitialize)(this.dgdFunctionArea)).EndInit();

this.ResumeLayout(false);



}

#endregion



/// <summary>

/// 应用程序的主入口点。

/// </summary>

[STAThread]

static void Main()

{

Application.Run(new Form1());

}

//初始化DataGrid

private void PopulateGrid()

{

//创建一个DataTable对象，包括四列，前三列为String，最后一列为Boolean。

dtblFunctionalArea = new DataTable ("FunctionArea");

string[] arrstrFunctionalArea = new string [3]{"Functional Area","Min","Max"};

DataColumn dtCol = null;

//创建String列

for(int i=0; i< 3;i++)

{

dtCol = new DataColumn(arrstrFunctionalArea[i]);

dtCol.DataType = Type.GetType("System.String");

dtCol.DefaultValue = "";

dtblFunctionalArea.Columns.Add(dtCol);

}



//创建Boolean列，用CheckedBox来显示。

DataColumn dtcCheck = new DataColumn("IsMandatory");

dtcCheck.DataType = System.Type.GetType("System.Boolean");

dtcCheck.DefaultValue = false;

dtblFunctionalArea.Columns.Add(dtcCheck);



//把表绑定到DataGrid

dgdFunctionArea.DataSource = dtblFunctionalArea;



//为DataGrid加载DataGridTableStyle样式

if(!dgdFunctionArea.TableStyles.Contains("FunctionArea"))

{

DataGridTableStyle dgdtblStyle = new DataGridTableStyle();

dgdtblStyle.MappingName = dtblFunctionalArea.TableName;

dgdFunctionArea.TableStyles.Add(dgdtblStyle);

dgdtblStyle.RowHeadersVisible = false;

dgdtblStyle.HeaderBackColor = Color.LightSteelBlue;

dgdtblStyle.AllowSorting = false;

dgdtblStyle.HeaderBackColor = Color.FromArgb(8,36,107);

dgdtblStyle.RowHeadersVisible = false;

dgdtblStyle.HeaderForeColor = Color.White;

dgdtblStyle.HeaderFont = new System.Drawing.Font("Microsoft Sans Serif", 9F,

System.Drawing.FontStyle.Bold,

System.Drawing.GraphicsUnit.Point, ((System.Byte)(0)));

dgdtblStyle.GridLineColor = Color.DarkGray;

dgdtblStyle.PreferredRowHeight = 22;

dgdFunctionArea.BackgroundColor = Color.White;



//设置列的宽度

GridColumnStylesCollection colStyle = dgdFunctionArea.TableStyles[0].GridColumnStyles;

colStyle[0].Width = 100;

colStyle[1].Width = 50;

colStyle[2].Width = 50;

colStyle[3].Width = 80;

}



DataGridTextBoxColumn dgtb = (DataGridTextBoxColumn)dgdFunctionArea.TableStyles[0].GridColumnStyles[0];

ComboBox cmbFunctionArea = new ComboBox();

cmbFunctionArea.Items.AddRange(new object[]{"选项一","选项二","选项三"});

cmbFunctionArea.Cursor = Cursors.Arrow;

cmbFunctionArea.DropDownStyle= ComboBoxStyle.DropDownList;

cmbFunctionArea.Dock = DockStyle.Fill;

//在选定项发生更改并且提交了该更改后发生

cmbFunctionArea.SelectionChangeCommitted += new EventHandler(cmbFunctionArea_SelectionChangeCommitted);

//把ComboBox添加到DataGridTableStyle的第一列

dgtb.TextBox.Controls.Add(cmbFunctionArea);



}

//设置焦点模拟

private void GetFocus(int row,int col)

{

//先把焦点移动到DataGrid

this.dgdFunctionArea.Focus();

//把焦点移动到DataGridCell

DataGridCell dgc = new DataGridCell(row,col);

this.dgdFunctionArea.CurrentCell = dgc;

DataGridTextBoxColumn dgtb = (DataGridTextBoxColumn)dgdFunctionArea.TableStyles[0].GridColumnStyles[col];

//设置焦点

dgtb.TextBox.Focus();



}

//把Combobox上修改的数据提交到当前的网格

private void cmbFunctionArea_SelectionChangeCommitted(object sender, EventArgs e)

{

this.dgdFunctionArea[this.dgdFunctionArea.CurrentCell] = ((ComboBox)sender).SelectedItem.ToString();

}

//设置新的焦点

private void buttonFocus_Click(object sender, System.EventArgs e)

{

//焦点模拟,这里设置第三行第一列

GetFocus(2,0);

}

}

}


下面是测试界面：





总结，这里是通过DataGridTextBoxColumn.TextBox.Controls.Add方法实现在列中添加ComboBox控件；对于数据的保存是使用ComboBox.SelectionChangeCommitted事件来完成；设置焦点是通过DataGridTextBoxColumn.TextBox.Focus方法来实现。另外通过这个方法也可以添加DateTimePicker等类似的控件。