DataGridView.AutoGenerateColumns 屬性
定義
重要
部分資訊涉及發行前產品,在發行之前可能會有大幅修改。 Microsoft 對此處提供的資訊,不做任何明確或隱含的瑕疵擔保。
取得或設定值,指出當已設定 DataSource 或 DataMember 屬性時,是否會自動建立資料行。
public:
property bool AutoGenerateColumns { bool get(); void set(bool value); };
[System.ComponentModel.Browsable(false)]
public bool AutoGenerateColumns { get; set; }
[<System.ComponentModel.Browsable(false)>]
member this.AutoGenerateColumns : bool with get, set
Public Property AutoGenerateColumns As Boolean
屬性值
如果應該要自動建立資料行,則為true
;否則為 false
。 預設為 true
。
- 屬性
範例
下列程式碼範例示範如何在您設定 AutoGenerateColumnsfalse
為 時手動新增資料行,並將其系結至資料來源。 在此範例中, DataGridView 控制項會系結至商務物件清單 Task
。 然後,資料行會加入,並透過 DataGridViewColumn.DataPropertyName 屬性系結至 Task
屬性。 此範例是How to: Access Objects in a Windows Forms DataGridViewComboBoxCell Drop-Down List中較大型範例的一部分。
public class Form1 : Form
{
private List<Employee> employees = new List<Employee>();
private List<Task> tasks = new List<Task>();
private Button reportButton = new Button();
private DataGridView dataGridView1 = new DataGridView();
[STAThread]
public static void Main()
{
Application.Run(new Form1());
}
public Form1()
{
dataGridView1.Dock = DockStyle.Fill;
dataGridView1.AutoSizeColumnsMode =
DataGridViewAutoSizeColumnsMode.AllCells;
reportButton.Text = "Generate Report";
reportButton.Dock = DockStyle.Top;
reportButton.Click += new EventHandler(reportButton_Click);
Controls.Add(dataGridView1);
Controls.Add(reportButton);
Load += new EventHandler(Form1_Load);
Text = "DataGridViewComboBoxColumn Demo";
}
// Initializes the data source and populates the DataGridView control.
private void Form1_Load(object sender, EventArgs e)
{
PopulateLists();
dataGridView1.AutoGenerateColumns = false;
dataGridView1.DataSource = tasks;
AddColumns();
}
// Populates the employees and tasks lists.
private void PopulateLists()
{
employees.Add(new Employee("Harry"));
employees.Add(new Employee("Sally"));
employees.Add(new Employee("Roy"));
employees.Add(new Employee("Pris"));
tasks.Add(new Task(1, employees[1]));
tasks.Add(new Task(2));
tasks.Add(new Task(3, employees[2]));
tasks.Add(new Task(4));
}
// Configures columns for the DataGridView control.
private void AddColumns()
{
DataGridViewTextBoxColumn idColumn =
new DataGridViewTextBoxColumn();
idColumn.Name = "Task";
idColumn.DataPropertyName = "Id";
idColumn.ReadOnly = true;
DataGridViewComboBoxColumn assignedToColumn =
new DataGridViewComboBoxColumn();
// Populate the combo box drop-down list with Employee objects.
foreach (Employee e in employees) assignedToColumn.Items.Add(e);
// Add "unassigned" to the drop-down list and display it for
// empty AssignedTo values or when the user presses CTRL+0.
assignedToColumn.Items.Add("unassigned");
assignedToColumn.DefaultCellStyle.NullValue = "unassigned";
assignedToColumn.Name = "Assigned To";
assignedToColumn.DataPropertyName = "AssignedTo";
assignedToColumn.AutoComplete = true;
assignedToColumn.DisplayMember = "Name";
assignedToColumn.ValueMember = "Self";
// Add a button column.
DataGridViewButtonColumn buttonColumn =
new DataGridViewButtonColumn();
buttonColumn.HeaderText = "";
buttonColumn.Name = "Status Request";
buttonColumn.Text = "Request Status";
buttonColumn.UseColumnTextForButtonValue = true;
dataGridView1.Columns.Add(idColumn);
dataGridView1.Columns.Add(assignedToColumn);
dataGridView1.Columns.Add(buttonColumn);
// Add a CellClick handler to handle clicks in the button column.
dataGridView1.CellClick +=
new DataGridViewCellEventHandler(dataGridView1_CellClick);
}
// Reports on task assignments.
private void reportButton_Click(object sender, EventArgs e)
{
StringBuilder report = new StringBuilder();
foreach (Task t in tasks)
{
String assignment =
t.AssignedTo == null ?
"unassigned" : "assigned to " + t.AssignedTo.Name;
report.AppendFormat("Task {0} is {1}.", t.Id, assignment);
report.Append(Environment.NewLine);
}
MessageBox.Show(report.ToString(), "Task Assignments");
}
// Calls the Employee.RequestStatus method.
void dataGridView1_CellClick(object sender, DataGridViewCellEventArgs e)
{
// Ignore clicks that are not on button cells.
if (e.RowIndex < 0 || e.ColumnIndex !=
dataGridView1.Columns["Status Request"].Index) return;
// Retrieve the task ID.
Int32 taskID = (Int32)dataGridView1[0, e.RowIndex].Value;
// Retrieve the Employee object from the "Assigned To" cell.
Employee assignedTo = dataGridView1.Rows[e.RowIndex]
.Cells["Assigned To"].Value as Employee;
// Request status through the Employee object if present.
if (assignedTo != null)
{
assignedTo.RequestStatus(taskID);
}
else
{
MessageBox.Show(String.Format(
"Task {0} is unassigned.", taskID), "Status Request");
}
}
}
Public Class Form1
Inherits Form
Private employees As New List(Of Employee)
Private tasks As New List(Of Task)
Private WithEvents reportButton As New Button
Private WithEvents dataGridView1 As New DataGridView
<STAThread()> _
Public Sub Main()
Application.Run(New Form1)
End Sub
Sub New()
dataGridView1.Dock = DockStyle.Fill
dataGridView1.AutoSizeColumnsMode = _
DataGridViewAutoSizeColumnsMode.AllCells
reportButton.Text = "Generate Report"
reportButton.Dock = DockStyle.Top
Controls.Add(dataGridView1)
Controls.Add(reportButton)
Text = "DataGridViewComboBoxColumn Demo"
End Sub
' Initializes the data source and populates the DataGridView control.
Private Sub Form1_Load(ByVal sender As Object, _
ByVal e As EventArgs) Handles Me.Load
PopulateLists()
dataGridView1.AutoGenerateColumns = False
dataGridView1.DataSource = tasks
AddColumns()
End Sub
' Populates the employees and tasks lists.
Private Sub PopulateLists()
employees.Add(New Employee("Harry"))
employees.Add(New Employee("Sally"))
employees.Add(New Employee("Roy"))
employees.Add(New Employee("Pris"))
tasks.Add(New Task(1, employees(1)))
tasks.Add(New Task(2))
tasks.Add(New Task(3, employees(2)))
tasks.Add(New Task(4))
End Sub
' Configures columns for the DataGridView control.
Private Sub AddColumns()
Dim idColumn As New DataGridViewTextBoxColumn()
idColumn.Name = "Task"
idColumn.DataPropertyName = "Id"
idColumn.ReadOnly = True
Dim assignedToColumn As New DataGridViewComboBoxColumn()
' Populate the combo box drop-down list with Employee objects.
For Each e As Employee In employees
assignedToColumn.Items.Add(e)
Next
' Add "unassigned" to the drop-down list and display it for
' empty AssignedTo values or when the user presses CTRL+0.
assignedToColumn.Items.Add("unassigned")
assignedToColumn.DefaultCellStyle.NullValue = "unassigned"
assignedToColumn.Name = "Assigned To"
assignedToColumn.DataPropertyName = "AssignedTo"
assignedToColumn.AutoComplete = True
assignedToColumn.DisplayMember = "Name"
assignedToColumn.ValueMember = "Self"
' Add a button column.
Dim buttonColumn As New DataGridViewButtonColumn()
buttonColumn.HeaderText = ""
buttonColumn.Name = "Status Request"
buttonColumn.Text = "Request Status"
buttonColumn.UseColumnTextForButtonValue = True
dataGridView1.Columns.Add(idColumn)
dataGridView1.Columns.Add(assignedToColumn)
dataGridView1.Columns.Add(buttonColumn)
End Sub
' Reports on task assignments.
Private Sub reportButton_Click(ByVal sender As Object, _
ByVal e As EventArgs) Handles reportButton.Click
Dim report As New StringBuilder()
For Each t As Task In tasks
Dim assignment As String
If t.AssignedTo Is Nothing Then
assignment = "unassigned"
Else
assignment = "assigned to " + t.AssignedTo.Name
End If
report.AppendFormat("Task {0} is {1}.", t.Id, assignment)
report.Append(Environment.NewLine)
Next
MessageBox.Show(report.ToString(), "Task Assignments")
End Sub
' Calls the Employee.RequestStatus method.
Private Sub dataGridView1_CellClick(ByVal sender As Object, _
ByVal e As DataGridViewCellEventArgs) _
Handles dataGridView1.CellClick
' Ignore clicks that are not on button cells.
If e.RowIndex < 0 OrElse Not e.ColumnIndex = _
dataGridView1.Columns("Status Request").Index Then Return
' Retrieve the task ID.
Dim taskID As Int32 = CInt(dataGridView1(0, e.RowIndex).Value)
' Retrieve the Employee object from the "Assigned To" cell.
Dim assignedTo As Employee = TryCast(dataGridView1.Rows(e.RowIndex) _
.Cells("Assigned To").Value, Employee)
' Request status through the Employee object if present.
If assignedTo IsNot Nothing Then
assignedTo.RequestStatus(taskID)
Else
MessageBox.Show(String.Format( _
"Task {0} is unassigned.", taskID), "Status Request")
End If
End Sub
End Class
備註
當此屬性設定為 true
且 DataSource 或 DataMember 屬性已設定或變更時,系統會自動產生資料行。 當 屬性從 false
變更為 true
時 AutoGenerateColumns ,也可以自動產生資料行。 如果此屬性為 true
且 DataSource 變更,因此有不符合先前 DataSource 值之資料行的資料行,則會捨棄不相符資料行中的資料。 如果未設定 或 DataMember 屬性, DataSource 則會忽略這個屬性。
當 設定為 true
時 AutoGenerateColumns , DataGridView 控制項會針對資料來源中物件的每個公用屬性產生一個資料行。 如果系結物件實作 ICustomTypeDescriptor 介面,控制項會針對 方法所 GetProperties 傳回的每個屬性產生一個資料行。 每個資料行標頭都會包含資料行所代表之屬性名稱的值。
如果您將 屬性 AutoGenerateColumns 設定為 DataSourcefalse
,則必須手動新增資料行。 您可以將屬性設定 DataGridViewColumn.DataPropertyName 為系結物件所公開的屬性名稱,將每個加入的資料行系結至資料來源。
注意
在 Windows Forms Designer 中設定 , DataSource 會自動將 AutoGenerateColumns 屬性設定為 false
,並產生程式碼,以新增和系結資料來源中每個屬性的資料行。 在設計階段產生的程式碼相當於下列範例所示的手動加入程式碼。 它與執行時間的自動產生資料行不同,當 屬性設定為 true
時發生。 AutoGenerateColumns