在DataGrid中簡單使用下拉列表框

作者：Tushar Ameta

翻譯：秋楓

在DataGrid中使用下拉列表問題。這篇文章講了如何在 System.Windows.Forms.DataGrid中切入使用ComboBox控件。不過原文不全，無法調試，在這里為了說清楚點，對原文作了一些修改，整篇文章主要包括三方面的內容。

1． 在DataGrid中加入ComboBox列；

2． 把在DataGrid中的修改保存到對應的網格；

3． 設置DataGrid中網格的焦點。



下面是整個源代碼，一些功能可以看注釋。

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 窗體設計器生成的代碼

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 = "獲取焦點";

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>

/// 應用程序的主入口點。

/// </summary>

[STAThread]

static void Main()

{

Application.Run(new Form1());

}

//初始化DataGrid

private void PopulateGrid()

{

//創建一個DataTable對象，包括四列，前三列為String，最后一列為Boolean。

dtblFunctionalArea = new DataTable ("FunctionArea");

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

DataColumn dtCol = null;

//創建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);

}



//創建Boolean列，用CheckedBox來顯示。

DataColumn dtcCheck = new DataColumn("IsMandatory");

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

dtcCheck.DefaultValue = false;

dtblFunctionalArea.Columns.Add(dtcCheck);



//把表綁定到DataGrid

dgdFunctionArea.DataSource = dtblFunctionalArea;



//為DataGrid加載DataGridTableStyle樣式

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;



//設置列的寬度

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[]{"選項一","選項二","選項三"});

cmbFunctionArea.Cursor = Cursors.Arrow;

cmbFunctionArea.DropDownStyle= ComboBoxStyle.DropDownList;

cmbFunctionArea.Dock = DockStyle.Fill;

//在選定項發生更改并且提交了該更改后發生

cmbFunctionArea.SelectionChangeCommitted += new EventHandler(cmbFunctionArea_SelectionChangeCommitted);

//把ComboBox添加到DataGridTableStyle的第一列

dgtb.TextBox.Controls.Add(cmbFunctionArea);



}

//設置焦點模擬

private void GetFocus(int row,int col)

{

//先把焦點移動到DataGrid

this.dgdFunctionArea.Focus();

//把焦點移動到DataGridCell

DataGridCell dgc = new DataGridCell(row,col);

this.dgdFunctionArea.CurrentCell = dgc;

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

//設置焦點

dgtb.TextBox.Focus();



}

//把Combobox上修改的數據提交到當前的網格

private void cmbFunctionArea_SelectionChangeCommitted(object sender, EventArgs e)

{

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

}

//設置新的焦點

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

{

//焦點模擬,這里設置第三行第一列

GetFocus(2,0);

}

}

}


下面是測試界面：





總結，這里是通過DataGridTextBoxColumn.TextBox.Controls.Add方法實現在列中添加ComboBox控件；對于數據的保存是使用ComboBox.SelectionChangeCommitted事件來完成；設置焦點是通過DataGridTextBoxColumn.TextBox.Focus方法來實現。另外通過這個方法也可以添加DateTimePicker等類似的控件。