Parameter.ToString Méthode

  • Référence

Définition

Espace de noms:
System.Web.UI.WebControls
Assembly:
System.Web.dll

Convertit la valeur de cette instance en sa représentation sous forme de chaîne équivalente.

public:
 override System::String ^ ToString();
public override string ToString ();
override this.ToString : unit -> string
Public Overrides Function ToString () As String

Retours

String

Représentation sous forme de chaîne de la valeur de cette instance.

Exemples

L’exemple de code suivant montre comment accéder aux différentes propriétés d’un Parameter objet, notamment ses Name propriétés et Type .

<%@ 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 Page_Load(object sender, EventArgs e) {

    SqlDataSource sqlSource = 
        new SqlDataSource(ConfigurationManager.ConnectionStrings["MyNorthwind"].ConnectionString,
                          "SELECT * From Employees where EmployeeID = @employee");
    
    // When a Parameter is not named, Name returns String.Empty.
    Parameter userID = new Parameter();

    if (userID.Name.Equals(String.Empty)) {
        Response.Write("Name is Empty<br />");
    }

    if (null == userID.Name) {
        Response.Write("Name is Null<br />");
    }

    // Set the Name of the Parameter
    userID.Name = "employee";

    // The Parameter.DefaultValue property is used to bind a static String.
    userID.DefaultValue = "3";

    // The ToString method returns the Name of the Parameter.
    Response.Write(userID.ToString() + "<br />");
    Response.Write(userID.Name + "<br />");

    // The default Type of the Parameter is TypeCode.Object
    Response.Write(userID.Type.ToString() + "<br />");

    sqlSource.SelectParameters.Add(userID);
    Page.Controls.Add(sqlSource);

    GridView grid = new GridView();
    grid.DataSource = sqlSource;
    grid.DataBind();

    PlaceHolder1.Controls.Add(grid);
}
</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:PlaceHolder id="PlaceHolder1" runat="server"/>

        </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 Page_Load(ByVal sender As Object, ByVal e As EventArgs)

    Dim sqlSource As New SqlDataSource
    sqlSource.ConnectionString = _
        ConfigurationManager.ConnectionStrings("MyNorthwind").ConnectionString

    sqlSource.SelectCommand = _
        "SELECT * From Employees where EmployeeID = @employee"


    ' When a Parameter is not named, Name returns String.Empty.
    Dim userID As New Parameter()

    If userID.Name Is String.Empty Then
        Response.Write("Name is Empty<br />")
    End If

    If userID.Name Is Nothing Then
        Response.Write("Name is Null<br />")
    End If

    ' Set the Name of the Parameter
    userID.Name = "employee"

    ' The Parameter.DefaultValue property is used to bind a static String
    userID.DefaultValue = "3"

    ' The ToString method returns the Name of the Parameter
    Response.Write(userID.ToString & "<br />")
    Response.Write(userID.Name & "<br />")

    ' The default Type of the Parameter is TypeCode.Object
    Response.Write(userID.Type.ToString & "<br />")

    sqlSource.SelectParameters.Add(userID)
    Page.Controls.Add(sqlSource)

    Dim grid As New GridView()
    grid.DataSource = sqlSource
    grid.DataBind()

    PlaceHolder1.Controls.Add(grid)

 End Sub 'Page_Load
</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:PlaceHolder id="PlaceHolder1" runat="server"/>

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

Remarques

La ToString méthode retourne la Name propriété de l’objet Parameter . Si l’objet Parameter n’a pas de nom, ToString retourne String.Empty.

S’applique à

Voir aussi