SqlDataSourceStatusEventArgs.Command Propriedade

Definição

Obtém o comando de banco de dados enviado para o banco de dados.Gets the database command submitted to the database.

public:
 property System::Data::Common::DbCommand ^ Command { System::Data::Common::DbCommand ^ get(); };
public System.Data.Common.DbCommand Command { get; }
member this.Command : System.Data.Common.DbCommand
Public ReadOnly Property Command As DbCommand

Valor da propriedade

DbCommand

O DbCommand objeto que representa o comando de banco de dados enviado ao banco de dados.The DbCommand object that represents the database command submitted to the database.

Exemplos

O exemplo de código a seguir demonstra como examinar os valores dos parâmetros de saída ao usar um SqlDataSource controle com um procedimento armazenado.The following code example demonstrates how to examine the values of output parameters when using a SqlDataSource control with a stored procedure. A SelectParameters coleção contém os parâmetros que o SqlDataSource usa para o procedimento armazenado e consiste em parâmetros que passam informações do formulário da Web para o procedimento armazenado, bem como parâmetros que passam informações de volta para o formulário.The SelectParameters collection contains the parameters that the SqlDataSource uses for the stored procedure, and consists of parameters that pass information from the Web form to the stored procedure as well as parameters that pass information back to the form. Este exemplo de código faz parte de um exemplo maior fornecido para a SqlDataSourceStatusEventArgs classe.This code example is part of a larger example provided for the SqlDataSourceStatusEventArgs class.

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

<script runat="server">
// Clicking the Submit button explicitly refreshes the data 
// by calling the Select() method.
private void Submit(Object source, EventArgs e) {
  SqlDataSource1.Select(DataSourceSelectArguments.Empty);
}

// This event handler is called after the Select() method is executed.
private void OnSelectedHandler(Object source, SqlDataSourceStatusEventArgs e) {

  IDbCommand cmd = e.Command; 
  
  Label1.Text = "Parameter return values: ";

  foreach (SqlParameter param in cmd.Parameters) {
    //  Extract the value of the parameter.
    Label1.Text += param.ParameterName + " - " + param.Value.ToString();
  }
}
</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"
            datasourcemode="DataSet"
            connectionstring="<%$ ConnectionStrings:MyNorthwind%>"
            selectcommand="getordertotal"
            onselected="OnSelectedHandler">
            <selectparameters>
              <asp:querystringparameter name="empId" querystringfield="empId" />
              <asp:parameter name="total" type="Int32" direction="Output" defaultvalue="0" />
              <asp:parameter name="_ret" type="Int32" direction="ReturnValue" defaultvalue="0" />
            </selectparameters>
        </asp:sqldatasource>
        <!--
          CREATE PROCEDURE dbo.getordertotal
            @empId int,
            @total int OUTPUT
          as
            set nocount on
            select @total    = count(1) from orders where employeeid=@empid;
            select * from orders where employeeID = @empId ;
            return (-1000);
          GO
        -->

        <asp:gridview
          id="GridView1"
          runat="server"
          allowpaging="True"
          pagesize="5"
          datasourceid="SqlDataSource1" />

        <asp:button
          id="Button1"
          runat="server"
          onclick="Submit"
          text="Refresh Data" />

        <asp:label id="Label1" runat="server" />

    </form>
  </body>
</html>
<%@Page  Language="VB" %>
<%@Import Namespace="System.Data" %>
<%@Import Namespace="System.Data.Common" %>
<%@Import Namespace="System.Data.SqlClient" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<script runat="server">
' Clicking the Submit button explicitly refreshes the data 
' by calling the Select() method.
Private Sub Submit(source As Object, e As EventArgs)
  
  SqlDataSource1.Select(DataSourceSelectArguments.Empty)
  
End Sub ' Submit

' This event handler is called after the Select() method is executed.
Private Sub OnSelectedHandler(source As Object, e As SqlDataSourceStatusEventArgs)

  Dim cmd As IDbCommand 
  cmd = e.Command
  Dim param As SqlParameter
  
  Label1.Text = "Parameter return values: "
  
  For Each param In cmd.Parameters
    
    ' Extract the name and value of the parameter.
    Label1.Text = Label1.Text & param.ParameterName & " - " & _
                  param.Value.ToString()

  Next

End Sub ' OnSelectedHandler
</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"
            datasourcemode="DataSet"
            connectionstring="<%$ ConnectionStrings:MyNorthwind%>"
            selectcommand="getordertotal"
            onselected="OnSelectedHandler">
            <selectparameters>
              <asp:querystringparameter name="empId" querystringfield="empId" />
              <asp:parameter name="total" type="Int32" direction="Output" defaultvalue="0" />
              <asp:parameter name="_ret" type="Int32" direction="ReturnValue" defaultvalue="0" />
            </selectparameters>
        </asp:sqldatasource>
        <!--
          CREATE PROCEDURE dbo.getordertotal
            @empId int,
            @total int OUTPUT
          as
            set nocount on
            select @total    = count(1) from orders where employeeid=@empid;
            select * from orders where employeeID = @empId ;
            return (-1000);
          GO
        -->

        <asp:gridview
          id="GridView1"
          runat="server"
          allowpaging="True"
          pagesize="5"
          datasourceid="SqlDataSource1" />

        <asp:button
          id="Button1"
          runat="server"
          onclick="Submit"
          text="Refresh Data" />

        <asp:label id="Label1" runat="server" />

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

Comentários

Você pode manipular o Selected evento,, Updated Inserted ou Deleted para examinar e manipular as propriedades do DbCommand depois que ele é enviado pelo SqlDataSource controle para o banco de dados.You can handle the Selected, Updated, Inserted, or Deleted event to examine and manipulate the properties of the DbCommand after it is submitted by the SqlDataSource control to the database. A Command propriedade permite que você acesse valores de retorno e valores em qualquer parâmetro de saída depois que a operação de banco de dados é executada por meio de sua Parameters propriedade, bem como a CommandText propriedade, que representa a consulta SQL, o comando ou o nome do procedimento armazenado que foi enviado ao banco de dados.The Command property enables you to access return values and values in any output parameters after the database operation is performed through its Parameters property, as well as the CommandText property, which represents the SQL query, command, or stored procedure name that was submitted to the database.

Todos os parâmetros de saída são especificamente de parâmetros que têm um InputOutput Output valor ou para a Direction Propriedade do Parameter objeto.Any output parameters are specifically from parameters that have an InputOutput or Output value for the Direction property of the Parameter object. Um valor de retorno é de um parâmetro que tem um ReturnValue valor.A return value is from a parameter that has a ReturnValue value.

Aplica-se a

Confira também