HttpSessionState.Add(String, Object) Méthode
Définition
Important
Certaines informations portent sur la préversion du produit qui est susceptible d’être en grande partie modifiée avant sa publication. Microsoft exclut toute garantie, expresse ou implicite, concernant les informations fournies ici.
Ajoute un nouvel élément à la collection des états de session.
public:
void Add(System::String ^ name, System::Object ^ value);
public void Add (string name, object value);
member this.Add : string * obj -> unit
Public Sub Add (name As String, value As Object)
Paramètres
- name
- String
Nom de l’élément à ajouter à la collection d’état de session.
- value
- Object
Valeur de l’élément à ajouter à la collection d’état de session.
Exemples
L’exemple suivant montre comment stocker des valeurs à l’état de session à l’aide de la Add méthode . Il montre également comment supprimer des valeurs à l’état de session à l’aide de la Remove méthode . Un Repeater contrôle est utilisé pour afficher l’état de la session de contenu sur la page web. La GetEnumerator méthode est utilisée pour itérer dans la collection d’états de session et remplir le Repeater contrôle.
Important
Cet exemple comprend une zone de texte qui accepte une entrée d'utilisateur, ce qui constitue une menace potentielle pour la sécurité. Par défaut, les pages web ASP.NET vérifient que l’entrée d’utilisateur n’inclut pas de script ou d’éléments HTML. Pour plus d’informations, consultez Vue d’ensemble des attaques de script.
<%@ 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">
protected void Button1_Click(object sender, EventArgs e)
{
// If both name and value are specified
// use the Add method to add the item to session-state.
if (!String.IsNullOrEmpty(TextBox1.Text) &
!String.IsNullOrEmpty(TextBox2.Text))
{
string itemName = Server.HtmlEncode(TextBox1.Text);
string itemValue = Server.HtmlEncode(TextBox2.Text);
Session.Add(itemName, itemValue);
// Refresh the Repeater control.
RefreshRepeater();
}
}
protected void RefreshRepeater()
{
// Use the GetEnumerator method to
// iterate through the session-state.
ArrayList values = new ArrayList();
System.Collections.IEnumerator ie = Session.GetEnumerator();
string currentSessionItemName;
while (ie.MoveNext())
{
currentSessionItemName = (string)ie.Current;
values.Add(new SessionDataDisplay(currentSessionItemName,
Session[currentSessionItemName].ToString()));
}
// Bind values ArrayList to Repeater control.
Repeater1.DataSource = values;
Repeater1.DataBind();
}
public class SessionDataDisplay
{
private string _name;
private string _value;
public SessionDataDisplay(string name, string value)
{
this._name = name;
this._value = value;
}
public string Name
{
get { return _name; }
}
public string Value
{
get { return _value; }
}
}
protected void Repeater1_ItemCommand(object source, RepeaterCommandEventArgs e)
{
// Determine which item to remove and
// use the Remove method to remove it.
RepeaterItem itemToRemove = e.Item;
string sessionItemToRemove =
((Label)itemToRemove.FindControl("Label1")).Text;
Session.Remove(sessionItemToRemove);
// Refresh the Repeater control.
RefreshRepeater();
}
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>HttpSessionState Example</title>
</head>
<body>
<form id="form1"
runat="server"
defaultbutton="Button1"
defaultfocus="TextBox1">
<div>
Name
<asp:TextBox ID="TextBox1"
runat="server"></asp:TextBox>
<br />
Value
<asp:TextBox ID="TextBox2"
runat="server"></asp:TextBox>
<asp:Button ID="Button1"
runat="server"
OnClick="Button1_Click"
Text="Add" />
<br />
<asp:Repeater ID="Repeater1" runat="server" OnItemCommand="Repeater1_ItemCommand">
<ItemTemplate>
<br />
SessionState Item Name:
<asp:Label ID="Label1"
runat="server"
Text='<%# DataBinder.Eval(Container.DataItem, "Name") %>'/>,
SessionState Item Value:
<asp:Label ID="Label2"
runat="server"
Text='<%# DataBinder.Eval(Container.DataItem, "Value") %>'/>
<asp:Button ID="RemoveItem"
Text="Remove"
runat="server" />
</ItemTemplate>
</asp:Repeater>
</div>
</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">
Protected Sub Button1_Click(ByVal sender As Object, ByVal e As System.EventArgs)
' If both name and value are specified
' use the Add method to add the item to session-state.
If (Not String.IsNullOrEmpty(TextBox1.Text) And _
Not String.IsNullOrEmpty(TextBox2.Text)) Then
Dim itemName As String = Server.HtmlEncode(TextBox1.Text)
Dim itemValue As String = Server.HtmlEncode(TextBox2.Text)
Session.Add(itemName, itemValue)
' Refresh the Repeater control.
RefreshRepeater()
End If
End Sub
Protected Sub RefreshRepeater()
' Use the GetEnumerator method to
' iterate through the session-state.
Dim values As ArrayList = New ArrayList()
Dim ie As System.Collections.IEnumerator = Session.GetEnumerator()
Dim currentSessionItemName As String
While (ie.MoveNext())
currentSessionItemName = CType(ie.Current, String)
values.Add(New SessionDataDisplay(currentSessionItemName, _
Session(currentSessionItemName).ToString()))
End While
' Bind values ArrayList to Repeater control.
Repeater1.DataSource = values
Repeater1.DataBind()
End Sub
Public Class SessionDataDisplay
Private _name As String
Private _value As String
Public Sub New(ByVal name As String, ByVal value As String)
Me._name = name
Me._value = value
End Sub
Public ReadOnly Property Name() As String
Get
Return _name
End Get
End Property
Public ReadOnly Property Value() As String
Get
Return _value
End Get
End Property
End Class
Protected Sub Repeater1_ItemCommand(ByVal source As Object, _
ByVal e As System.Web.UI.WebControls.RepeaterCommandEventArgs)
' Determine which item to remove and
' use the Remove method to remove it.
Dim itemToRemove As RepeaterItem = e.Item
Dim sessionItemToRemove As String = _
CType(itemToRemove.FindControl("Label1"), Label).Text
Session.Remove(sessionItemToRemove)
' Refresh the Repeater control.
RefreshRepeater()
End Sub
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>HttpSessionState Example</title>
</head>
<body>
<form id="form1"
runat="server"
defaultbutton="Button1"
defaultfocus="TextBox1">
<div>
Name
<asp:TextBox ID="TextBox1"
runat="server"></asp:TextBox>
<br />
Value
<asp:TextBox ID="TextBox2"
runat="server"></asp:TextBox>
<asp:Button ID="Button1"
runat="server"
OnClick="Button1_Click"
Text="Add" />
<br />
<asp:Repeater ID="Repeater1" runat="server" OnItemCommand="Repeater1_ItemCommand">
<ItemTemplate>
<br />
SessionState Item Name:
<asp:Label ID="Label1"
runat="server"
Text='<%# DataBinder.Eval(Container.DataItem, "Name") %>'/>,
SessionState Item Value:
<asp:Label ID="Label2"
runat="server"
Text='<%# DataBinder.Eval(Container.DataItem, "Value") %>'/>
<asp:Button ID="RemoveItem"
Text="Remove"
runat="server" />
</ItemTemplate>
</asp:Repeater>
</div>
</form>
</body>
</html>
Remarques
Si le name
paramètre fait référence à un élément d’état de session existant, l’élément existant est remplacé par le spécifié value
.