CommandField.CausesValidation Proprietà
Definizione
Importante
Alcune informazioni sono relative alla release non definitiva del prodotto, che potrebbe subire modifiche significative prima della release definitiva. Microsoft non riconosce alcuna garanzia, espressa o implicita, in merito alle informazioni qui fornite.
Ottiene o imposta un valore che indica se quando l'utente fa clic su un pulsante in un campo CommandField viene eseguita la convalida.
public:
virtual property bool CausesValidation { bool get(); void set(bool value); };public override bool CausesValidation { get; set; }member this.CausesValidation : bool with get, setPublic Overrides Property CausesValidation As BooleanValore della proprietà
true per eseguire la convalida quando l'utente fa clic su un pulsante in un campo CommandField; in caso contrario, false. Il valore predefinito è true.
Esempio
Nell'esempio di codice seguente viene illustrato come utilizzare la CausesValidation proprietà per impedire che si verifichi la convalida quando si fa clic su un pulsante in un CommandField campo.
Importante
L'esempio include una casella di testo che accetta l'input dell'utente e rappresenta quindi una potenziale minaccia alla sicurezza. Per impostazione predefinita, le pagine Web ASP.NET verificano che l'input dell'utente non includa script o elementi HTML. Per altre informazioni, vedere Cenni preliminari sugli attacchi tramite script.
<%@ Page language="C#" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>CommandField CausesValidation Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>CommandField CausesValidation Example</h3>
<!-- Normally, the validation controls declared in the -->
<!-- EditItemTemplate of each TemplateField field column would -->
<!-- prevent the user from leaving a field value empty; however, -->
<!-- because the CausesValidation property of the CommandField -->
<!-- field column is set to false, validation does not occur when -->
<!-- the user clicks a button in the CommandField field column. -->
<asp:gridview id="CustomerGridView"
datasourceid="CustomersSqlDataSource"
autogeneratecolumns="false"
datakeynames="CustomerID"
cellpadding="10"
runat="server">
<columns>
<asp:commandfield showeditbutton="true"
causesvalidation="false"
headertext="Edit"/>
<asp:boundfield datafield="CustomerID"
headertext="Customer ID"
readonly="true"/>
<asp:templatefield headertext="Company Name"
itemstyle-verticalalign="Top">
<itemtemplate>
<%#Eval("CompanyName")%>
</itemtemplate>
<edititemtemplate>
<asp:textbox id="CompanyNameTextBox"
text='<%#Bind("CompanyName")%>'
width="90"
runat="server"/>
<br/>
<asp:requiredfieldvalidator id="CompanyNameRequiredValidator"
controltovalidate="CompanyNameTextBox"
display="Dynamic"
text="Please enter the company name."
runat="server"/>
</edititemtemplate>
</asp:templatefield>
<asp:templatefield headertext="Address"
itemstyle-verticalalign="Top">
<itemtemplate>
<%#Eval("Address")%>
</itemtemplate>
<edititemtemplate>
<asp:textbox id="AddressTextBox"
text='<%#Bind("Address")%>'
width="90"
runat="server"/>
<br/>
<asp:requiredfieldvalidator id="AddressRequiredValidator"
controltovalidate="AddressTextBox"
display="Dynamic"
text="Please enter the address."
runat="server"/>
</edititemtemplate>
</asp:templatefield>
<asp:templatefield headertext="City"
itemstyle-verticalalign="Top">
<itemtemplate>
<%#Eval("City")%>
</itemtemplate>
<edititemtemplate>
<asp:textbox id="CityTextBox"
text='<%#Bind("City")%>'
width="90"
runat="server"/>
<br/>
<asp:requiredfieldvalidator id="CityRequiredValidator"
controltovalidate="CityTextBox"
display="Dynamic"
text="Please enter the city."
runat="server"/>
</edititemtemplate>
</asp:templatefield>
</columns>
</asp:gridview>
<!-- This example uses Microsoft SQL Server and connects -->
<!-- to the Northwind sample database. Use an ASP.NET -->
<!-- expression to retrieve the connection string value -->
<!-- from the Web.config file. -->
<asp:sqldatasource id="CustomersSqlDataSource"
selectcommand="Select [CustomerID], [CompanyName], [Address], [City] From [Customers]"
updatecommand="Update [Customers] Set [CompanyName]=@CompanyName, [Address]=@Address, [City]=@City Where [CustomerID] = @CustomerID"
connectionstring="<%$ ConnectionStrings:NorthWindConnectionString%>"
runat="server">
</asp:sqldatasource>
</form>
</body>
</html>
<%@ Page language="VB" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>CommandField CausesValidation Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>CommandField CausesValidation Example</h3>
<!-- Normally, the validation controls declared in the -->
<!-- EditItemTemplate of each TemplateField field column would -->
<!-- prevent the user from leaving a field value empty; however, -->
<!-- because the CausesValidation property of the CommandField -->
<!-- field column is set to false, validation does not occur when -->
<!-- the user clicks a button in the CommandField field column. -->
<asp:gridview id="CustomerGridView"
datasourceid="CustomersSqlDataSource"
autogeneratecolumns="false"
datakeynames="CustomerID"
cellpadding="10"
runat="server">
<columns>
<asp:commandfield showeditbutton="true"
causesvalidation="false"
headertext="Edit"/>
<asp:boundfield datafield="CustomerID"
headertext="Customer ID"
readonly="true"/>
<asp:templatefield headertext="Company Name"
itemstyle-verticalalign="Top">
<itemtemplate>
<%#Eval("CompanyName")%>
</itemtemplate>
<edititemtemplate>
<asp:textbox id="CompanyNameTextBox"
text='<%#Bind("CompanyName")%>'
width="90"
runat="server"/>
<br/>
<asp:requiredfieldvalidator id="CompanyNameRequiredValidator"
controltovalidate="CompanyNameTextBox"
display="Dynamic"
text="Please enter the company name."
runat="server"/>
</edititemtemplate>
</asp:templatefield>
<asp:templatefield headertext="Address"
itemstyle-verticalalign="Top">
<itemtemplate>
<%#Eval("Address")%>
</itemtemplate>
<edititemtemplate>
<asp:textbox id="AddressTextBox"
text='<%#Bind("Address")%>'
width="90"
runat="server"/>
<br/>
<asp:requiredfieldvalidator id="AddressRequiredValidator"
controltovalidate="AddressTextBox"
display="Dynamic"
text="Please enter the address."
runat="server"/>
</edititemtemplate>
</asp:templatefield>
<asp:templatefield headertext="City"
itemstyle-verticalalign="Top">
<itemtemplate>
<%#Eval("City")%>
</itemtemplate>
<edititemtemplate>
<asp:textbox id="CityTextBox"
text='<%#Bind("City")%>'
width="90"
runat="server"/>
<br/>
<asp:requiredfieldvalidator id="CityRequiredValidator"
controltovalidate="CityTextBox"
display="Dynamic"
text="Please enter the city."
runat="server"/>
</edititemtemplate>
</asp:templatefield>
</columns>
</asp:gridview>
<!-- This example uses Microsoft SQL Server and connects -->
<!-- to the Northwind sample database. Use an ASP.NET -->
<!-- expression to retrieve the connection string value -->
<!-- from the Web.config file. -->
<asp:sqldatasource id="CustomersSqlDataSource"
selectcommand="Select [CustomerID], [CompanyName], [Address], [City] From [Customers]"
updatecommand="Update [Customers] Set [CompanyName]=@CompanyName, [Address]=@Address, [City]=@City Where [CustomerID] = @CustomerID"
connectionstring="<%$ ConnectionStrings:NorthWindConnectionString%>"
runat="server">
</asp:sqldatasource>
</form>
</body>
</html>
Commenti
Utilizzare la CausesValidation proprietà per specificare se viene eseguita la convalida quando si fa clic su un pulsante in un CommandField campo. Quando questa proprietà è impostata su true, per impostazione predefinita vengono convalidati tutti i controlli di convalida nella pagina. Per limitare la convalida solo a un determinato gruppo di controlli di convalida, creare un gruppo di convalida e quindi impostare la ValidationGroup proprietà sul nome del gruppo di convalida. Per altre informazioni sui gruppi di convalida, vedere BaseValidator.ValidationGroup.