CommandField.CausesValidation Property

Reference

Definition

Namespace:: System.Web.UI.WebControls

Assembly:: System.Web.dll

Important

Some information relates to prerelease product that may be substantially modified before it’s released. Microsoft makes no warranties, express or implied, with respect to the information provided here.

Gets or sets a value indicating whether validation is performed when the user clicks a button in a CommandField field.

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

Property Value

Boolean

true to perform validation when the user clicks a button in a CommandField field; otherwise, false. The default is true.

Examples

The following code example demonstrates how to use the CausesValidation property to prevent validation from occurring when a button in a CommandField field is clicked.

Important

This example has a text box that accepts user input, which is a potential security threat. By default, ASP.NET Web pages validate that user input does not include script or HTML elements. For more information, see Script Exploits Overview.

<%@ 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>

Remarks

Use the CausesValidation property to specify whether validation is performed when a button in a CommandField field is clicked. When this property is set to true, by default all validation controls on the page are validated. To limit validation to only a certain group of validation controls, create a validation group and then set the ValidationGroup property to the validation group's name. For more information on validation groups, see BaseValidator.ValidationGroup.

Applies to

Delen via