แก้ไข

แชร์ผ่าน

SqlDataSourceView.DeleteParameters Property

  • Reference

Definition

Namespace:
System.Web.UI.WebControls
Assembly:
System.Web.dll

Gets the parameters collection containing the parameters that are used by the DeleteCommand property.

public:
 property System::Web::UI::WebControls::ParameterCollection ^ DeleteParameters { System::Web::UI::WebControls::ParameterCollection ^ get(); };
[System.Web.UI.PersistenceMode(System.Web.UI.PersistenceMode.InnerProperty)]
public System.Web.UI.WebControls.ParameterCollection DeleteParameters { get; }
[<System.Web.UI.PersistenceMode(System.Web.UI.PersistenceMode.InnerProperty)>]
member this.DeleteParameters : System.Web.UI.WebControls.ParameterCollection
Public ReadOnly Property DeleteParameters As ParameterCollection

Property Value

ParameterCollection

A ParameterCollection that contains the parameters used by the DeleteCommand property.

Attributes
PersistenceModeAttribute

Examples

The following code example demonstrates how to set the DeleteCommand text to delete an order from the Northwind database. Initially, data is retrieved from the Orders table and displayed in a DropDownList control. You must explicitly declare the DeleteParameters property and call the Delete method when using data-bound controls, such as the DropDownList (unlike controls, such as the GridView and DetailsView, which automatically populate the parameters and call the Delete method on a data source control). In this example, the OnClick event is delegated to the private OnDeleted event handler, which explicitly calls the Delete method of the SqlDataSource control.

<%@Page  Language="C#" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<script runat="server">
private void OnDelete(Object sender, EventArgs e) {
    SqlDataSource1.Delete();
}
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
    <head runat="server">
    <title>ASP.NET Example</title>
</head>
<body>
        <form id="form1" runat="server">

            <asp:SqlDataSource
                id="SqlDataSource1"
                runat="server"
                ConnectionString="<%$ ConnectionStrings:MyNorthwind%>"
                SelectCommand="SELECT OrderID FROM Orders"
                DeleteCommand="DELETE FROM [Order Details] WHERE OrderID=@OrderID;DELETE FROM Orders WHERE OrderID=@OrderID;">
                <DeleteParameters>
                    <asp:ControlParameter Name="OrderID" ControlId="DropDownList1" PropertyName="SelectedValue" />
                </DeleteParameters>
            </asp:SqlDataSource>

            <asp:DropDownList
                id="DropDownList1"
                runat="server"
                DataTextField="OrderID"
                DataValueField="OrderID"
                DataSourceID="SqlDataSource1">
            </asp:DropDownList>

            <asp:Button
                id="Button1"
                runat="server"
                Text="Delete Order"
                OnClick="OnDelete">
            </asp:Button>

        </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">

<script runat="server">
 Sub On_Delete(ByVal sender As Object, ByVal e As EventArgs)
    SqlDataSource1.Delete()
 End Sub 'On_Delete
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
    <head>
    <title>ASP.NET Example</title>
</head>

    <body>
        <form id="form1" runat="server">

            <asp:SqlDataSource
                id="SqlDataSource1"
                runat="server"
                ConnectionString="<%$ ConnectionStrings:MyNorthwind%>"
                SelectCommand="SELECT OrderID FROM Orders"
                DeleteCommand="DELETE FROM [Order Details] WHERE OrderID=@OrderID;DELETE FROM Orders WHERE OrderID=@OrderID;">
                <DeleteParameters>
                    <asp:ControlParameter Name="OrderID" ControlId="DropDownList1" PropertyName="SelectedValue" />
                </DeleteParameters>
            </asp:SqlDataSource>

            <asp:DropDownList
                id="DropDownList1"
                runat="server"
                DataTextField="OrderID"
                DataValueField="OrderID"
                DataSourceID="SqlDataSource1">
            </asp:DropDownList>

            <asp:Button
                id="Button1"
                runat="server"
                Text="Delete Order"
                OnClick="On_Delete">
            </asp:Button>

        </form>
    </body>
</html>

Remarks

If the DeleteCommand property contains a parameterized SQL query, the DeleteParameters collection contains any Parameter objects that correspond to the parameter placeholders in the SQL string.

Parameter names might be affected by the OldValuesParameterFormatString property; specifically, if the name identifies a primary key, such as a key that is specified using the DataKeyNames property of a data-bound control, or in delete and update scenarios in which the ConflictDetection property is set to the CompareAllValues value and a set of oldValues is passed to the corresponding data method. In this case, the format string is applied to each parameter name in the oldValues collection.

Depending on the ADO.NET provider, the order of the parameters in the DeleteParameters collection might be important. The System.Data.OleDb and System.Data.Odbc providers associate the parameters in the collection according to the order that the parameters appear in the parameterized SQL query. The System.Data.SqlClient provider, which is the default ADO.NET provider for the SqlDataSource control, associates the parameters in the collection by matching the name of the parameter with the placeholder in the SQL query. For more information on parameterized SQL queries and commands, see Using Parameters with the SqlDataSource Control.

Applies to

See also