CommandField.CausesValidation Proprietà

Definizione

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, set
Public Overrides Property CausesValidation As Boolean

Valore 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 usare la CausesValidation proprietà per impedire che si verifichi la convalida quando viene fatto 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 proprietà per specificare se viene eseguita la CausesValidation convalida quando viene fatto 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.

Si applica a

Vedi anche