DataControlFieldCollection.Item[Int32] プロパティ
定義
重要
一部の情報は、リリース前に大きく変更される可能性があるプレリリースされた製品に関するものです。 Microsoft は、ここに記載されている情報について、明示または黙示を問わず、一切保証しません。
コレクション内の指定したインデックスでの DataControlField オブジェクトを取得または設定します。
public:
property System::Web::UI::WebControls::DataControlField ^ default[int] { System::Web::UI::WebControls::DataControlField ^ get(int index); };[System.ComponentModel.Browsable(false)]
public System.Web.UI.WebControls.DataControlField this[int index] { get; }[<System.ComponentModel.Browsable(false)>]
member this.Item(int) : System.Web.UI.WebControls.DataControlFieldDefault Public ReadOnly Property Item(index As Integer) As DataControlFieldパラメーター
- index
- Int32
コレクションから取得する DataControlField の 0 から始まるインデックス番号。
プロパティ値
コレクション内の指定したインデックス位置の DataControlField。
- 属性
例
次のコード例では、ユーザーがコントロール内のボタンを Item[] クリックしたときにインデクサーを使用してコントロールの GridView フィールドにアクセスする方法を示します。
<%@ Page language="C#" %>
<script runat="server">
void AuthorsGridView_RowCommand(Object sender, GridViewCommandEventArgs e)
{
// If multiple ButtonField columns are used, use the
// CommandName property to determine which button was clicked.
switch(e.CommandName)
{
case "Edit":
AuthorsGridView.Columns[0].Visible = false;
AuthorsGridView.Columns[1].Visible = true;
break;
case "Update":
AuthorsGridView.Columns[0].Visible = true;
AuthorsGridView.Columns[1].Visible = false;
break;
default:
// Do nothing.
break;
}
}
void AuthorsGridView_RowUpdating (Object sender, GridViewUpdateEventArgs e)
{
// Retrieve the row being edited.
int index = AuthorsGridView.EditIndex;
GridViewRow row = AuthorsGridView.Rows[index];
// Retrieve the new value for the author's first name from the row.
// In this example, the author's first name is in the second cell
// of the row (index 1). To get the value, first retrieve the TextBox
// that contains the value.
TextBox firstNameTextBox = (TextBox)row.Cells[1].FindControl("FirstNameTextBox");
// Make sure the control was found.
String firstName = "";
if(firstNameTextBox != null)
{
firstName = firstNameTextBox.Text;
}
// Retrieve the new value for the author's last name from the row.
// In this example, the author's last name is in the third cell
// of the row (index 2).
TextBox lastNameTextBox = (TextBox)row.Cells[2].FindControl("LastNameTextBox");
String lastName = "";
if(lastNameTextBox != null)
{
lastName = lastNameTextBox.Text;
}
// Because custom TemplateField field columns are used, parameters
// are not automatically created and passed to the data source control.
// Create Parameter objects to represent the fields to update and
// add the Parameter objects to the UpdateParameters collection.
Parameter lastNameParameter = new Parameter("au_lname", TypeCode.String, lastName);
Parameter firstNameParameter = new Parameter("au_fname", TypeCode.String, firstName);
// Clear the UpdateParameters collection before adding the
// Parameter objects. Otherwise, there will be duplicate
// parameters.
AuthorsSqlDataSource.UpdateParameters.Clear();
AuthorsSqlDataSource.UpdateParameters.Add(lastNameParameter);
AuthorsSqlDataSource.UpdateParameters.Add(firstNameParameter);
}
</script>
<head runat="server">
<title>ButtonFieldBase CausesValidation Example</title>
</head>
<body>
<form id="form1" runat="server">
<div>
<h3>ButtonFieldBase CausesValidation Example</h3>
<!-- Populate the Columns collection declaratively. -->
<asp:gridview id="AuthorsGridView"
datasourceid="AuthorsSqlDataSource"
cellpadding="5"
autogeneratecolumns="false"
datakeynames="au_id"
onrowcommand="AuthorsGridView_RowCommand"
onrowupdating="AuthorsGridView_RowUpdating"
runat="server">
<columns>
<asp:buttonfield commandname="Edit"
causesvalidation="false"
text="Edit"
headertext="Edit Author">
</asp:buttonfield>
<asp:buttonfield commandname="Update"
visible="false"
causesvalidation="true"
text="Update"
validationgroup="NameGroup"
headertext="Update Author">
</asp:buttonfield>
<asp:templatefield headertext="Last Name">
<itemtemplate>
<%# Eval("au_lname") %>
</itemtemplate>
<edititemtemplate>
<asp:textbox id="LastNameTextBox"
text='<%# Eval("au_lname") %>'
width="175"
runat="server" /><br />
<asp:RequiredFieldValidator ID="LastNameRequiredValidator"
ControlToValidate="LastNameTextBox"
ErrorMessage="Please enter a last name."
ValidationGroup="NameGroup"
Runat="server" />
</edititemtemplate>
</asp:templatefield>
<asp:templatefield headertext="First Name">
<itemtemplate>
<%# Eval("au_fname") %>
</itemtemplate>
<edititemtemplate>
<asp:textbox id="FirstNameTextBox"
text='<%# Eval("au_fname") %>'
width="175"
runat="server" /><br />
<asp:RequiredFieldValidator ID="FirstNameRequiredValidator"
ControlToValidate="FirstNameTextBox"
ErrorMessage="Please enter a first name."
ValidationGroup="NameGroup"
Runat="server" />
</edititemtemplate>
</asp:templatefield>
</columns>
</asp:gridview>
<!-- This example uses Microsoft SQL Server and connects -->
<!-- to the Pubs sample database. -->
<asp:sqldatasource id="AuthorsSqlDataSource"
selectcommand="SELECT [au_id], [au_lname], [au_fname] FROM [authors]"
updatecommand="UPDATE authors SET au_lname=@au_lname, au_fname=@au_fname WHERE (authors.au_id = @au_id)"
connectionstring="server=localhost;database=pubs;integrated security=SSPI"
runat="server">
</asp:sqldatasource>
</div>
</form>
</body>
</html>
<%@ Page language="VB" %>
<script runat="server">
Sub AuthorsGridView_RowCommand(ByVal sender As Object, ByVal e As GridViewCommandEventArgs)
' If multiple ButtonField columns are used, use the
' CommandName property to determine which button was clicked.
Select Case e.CommandName
Case "Edit"
AuthorsGridView.Columns(0).Visible = False
AuthorsGridView.Columns(1).Visible = True
Case "Update"
AuthorsGridView.Columns(0).Visible = True
AuthorsGridView.Columns(1).Visible = False
Case Else
' Do nothing.
End Select
End Sub
Sub AuthorsGridView_RowUpdating(ByVal sender As Object, ByVal e As GridViewUpdateEventArgs)
' Retrieve the row being edited.
Dim index As Integer = AuthorsGridView.EditIndex
Dim row As GridViewRow = AuthorsGridView.Rows(index)
' Retrieve the new value for the author's first name from the row.
' In this example, the author's first name is in the second cell
' of the row (index 1). To get the value, first retrieve the TextBox
' that contains the value.
Dim firstNameTextBox As TextBox = CType(row.Cells(1).FindControl("FirstNameTextBox"), TextBox)
' Make sure the control was found.
Dim firstName As String = ""
If Not firstNameTextBox Is Nothing Then
firstName = firstNameTextBox.Text
End If
' Retrieve the new value for the author's last name from the row.
' In this example, the author's last name is in the third cell
' of the row (index 2).
Dim lastNameTextBox As TextBox = CType(row.Cells(2).FindControl("LastNameTextBox"), TextBox)
Dim lastName As String = ""
If Not lastNameTextBox Is Nothing Then
lastName = lastNameTextBox.Text
End If
' Because custom TemplateField field columns are used, parameters
' are not automatically created and passed to the data source control.
' Create Parameter objects to represent the fields to update and
' add the Parameter objects to the UpdateParameters collection.
Dim lastNameParameter As New Parameter("au_lname", TypeCode.String, lastName)
Dim firstNameParameter As New Parameter("au_fname", TypeCode.String, firstName)
' Clear the UpdateParameters collection before adding the
' Parameter objects. Otherwise, there will be duplicate
' parameters.
AuthorsSqlDataSource.UpdateParameters.Clear()
AuthorsSqlDataSource.UpdateParameters.Add(lastNameParameter)
AuthorsSqlDataSource.UpdateParameters.Add(firstNameParameter)
End Sub
</script>
<head runat="server">
<title>ButtonFieldBase CausesValidation Example</title>
</head>
<body>
<form id="form1" runat="server">
<div>
<h3>ButtonFieldBase CausesValidation Example</h3>
<!-- Populate the Columns collection declaratively. -->
<asp:gridview id="AuthorsGridView"
datasourceid="AuthorsSqlDataSource"
cellpadding="5"
autogeneratecolumns="false"
datakeynames="au_id"
onrowcommand="AuthorsGridView_RowCommand"
onrowupdating="AuthorsGridView_RowUpdating"
runat="server">
<columns>
<asp:buttonfield commandname="Edit"
causesvalidation="false"
text="Edit"
headertext="Edit Author">
</asp:buttonfield>
<asp:buttonfield commandname="Update"
visible="false"
causesvalidation="true"
text="Update"
validationgroup="NameGroup"
headertext="Update Author">
</asp:buttonfield>
<asp:templatefield headertext="Last Name">
<itemtemplate>
<%# Eval("au_lname") %>
</itemtemplate>
<edititemtemplate>
<asp:textbox id="LastNameTextBox"
text='<%# Eval("au_lname") %>'
width="175"
runat="server" /><br />
<asp:RequiredFieldValidator ID="LastNameRequiredValidator"
ControlToValidate="LastNameTextBox"
ErrorMessage="Please enter a last name."
ValidationGroup="NameGroup"
Runat="server" />
</edititemtemplate>
</asp:templatefield>
<asp:templatefield headertext="First Name">
<itemtemplate>
<%# Eval("au_fname") %>
</itemtemplate>
<edititemtemplate>
<asp:textbox id="FirstNameTextBox"
text='<%# Eval("au_fname") %>'
width="175"
runat="server" /><br />
<asp:RequiredFieldValidator ID="FirstNameRequiredValidator"
ControlToValidate="FirstNameTextBox"
ErrorMessage="Please enter a first name."
ValidationGroup="NameGroup"
Runat="server" />
</edititemtemplate>
</asp:templatefield>
</columns>
</asp:gridview>
<!-- This example uses Microsoft SQL Server and connects -->
<!-- to the Pubs sample database. -->
<asp:sqldatasource id="AuthorsSqlDataSource"
selectcommand="SELECT [au_id], [au_lname], [au_fname] FROM [authors]"
updatecommand="UPDATE authors SET au_lname=@au_lname, au_fname=@au_fname WHERE (authors.au_id = @au_id)"
connectionstring="server=localhost;database=pubs;integrated security=SSPI"
runat="server">
</asp:sqldatasource>
</div>
</form>
</body>
</html>
注釈
配列表記を使用して、このインデクサーをDataControlFieldDataControlFieldCollection使用して、指定したインデックス位置にあるコレクションからオブジェクトを取得します。
適用対象
こちらもご覧ください
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