ASP.NET Tutorial/Sessions/Session class
Содержание
- 1 Session.Abandon()
- 2 Session.CodePage
- 3 Session.Contents.RemoveAll()
- 4 Session.CopyTo
- 5 Session.IsCookieless
- 6 Session.IsNewSession
- 7 Session.IsReadOnly
- 8 Session.Item
- 9 Session.Keys
- 10 Session.LCID
- 11 Session.Mode
- 12 Session.Remove
- 13 Session.RemoveAll
- 14 Session.RemoveAt
- 15 Session.StaticObjects
- 16 Session.Timeout
- 17 Use Session and Server.Transfer to create a wizard
Session.Abandon()
<source lang="csharp">
<%@ Page %> <script language="C#" runat="server"> private void Page_PreRender(object sender, EventArgs e) {
if(Session["UserName"] != null) UserNameLabel.Text = Session["UserName"].ToString();
} private void SaveButton_Click(object sender, System.EventArgs e) {
Session["UserName"] = UserNameTextBox.Text;
} private void AbandonButton_Click(object sender, System.EventArgs e) {
Session.Abandon();
} </script> <html>
<body>
<form id="form1" method="post" runat="server">
Update UserName in Session: <asp:TextBox id="UserNameTextBox" runat="server"></asp:TextBox>
<asp:Button id="SaveButton" runat="server" Text="Save" OnClick="SaveButton_Click"></asp:Button>
Current Session Contents:
<asp:Label ID="UserNameLabel" Runat="server" EnableViewState="False"></asp:Label>
<asp:Button id="RefreshButton" runat="server" Text="Refresh Without Saving"></asp:Button>
Abandon Session - takes effect on *next* request since current request is still referring to Session.
<asp:Button id="AbandonButton" runat="server" Text="Abandon Session" OnClick="AbandonButton_Click"></asp:Button>
<a href="Default.aspx">VB Version - same session</a>
</form>
</body>
</html></source>
Session.CodePage
<source lang="csharp">
<%@ Page Language="vb" %> <html>
<head>
<script runat="server">
Sub Page_Load()
Message.Text = "Current Code Page is: " & Session.CodePage
End Sub
</script>
</head>
<body>
<asp:label id="Message" runat="server"/>
</body> </html></source>
Session.Contents.RemoveAll()
<source lang="csharp">
<%@ Page Language="vb" %> <html>
<head>
<script runat="server">
Sub Page_Load()
Session.Contents.RemoveAll()
Message.Text = "Removed all items from current Session."
End Sub
</script>
</head>
<body>
<asp:label id="Message" runat="server"/>
</body> </html></source>
Session.CopyTo
<source lang="csharp">
<%@ Page Language="vb" %> <html>
<head>
<script runat="server">
Sub Page_Load()
If Session.Count > 0 Then
Dim myArray As Array = Array.CreateInstance(GetType(Object), _
Session.Count)
Session.CopyTo(myArray, 0)
Message.Text = "The first item in the array is: " & myArray(0)
End If
End Sub
</script>
</head>
<body>
<form runat="server">
<asp:label id="Message" runat="server"/>
</form>
</body> </html></source>
Session.IsCookieless
<source lang="csharp">
<%@ Page Language="vb" %> <html>
<head>
<script runat="server">
Sub Page_Load()
If Session.IsCookieless Then
Message.Text = "The current Session does not use cookies."
Else
Message.Text = "The current Session uses cookies."
End If
End Sub
</script>
</head>
<body>
<asp:label id="Message" runat="server"/>
</body> </html></source>
Session.IsNewSession
<source lang="csharp">
<%@ Page Language="vb" %> <html>
<head>
<script runat="server">
Sub Page_Load()
If Session.IsNewSession Then
"Session("foo") = "foo"
Message.Text = "The current Session (SessionID: " & _
Session.SessionID & ") was created with this request."
Else
Message.Text = "The current Session (SessionID: " & _
Session.SessionID & ") existed prior to this request."
End If
End Sub
</script>
</head>
<body>
<asp:label id="Message" runat="server"/>
</body> </html></source>
Session.IsReadOnly
<source lang="csharp">
<%@ Page Language="vb" EnableSessionState="ReadOnly" %> <html>
<head>
<script runat="server">
Sub Page_Load()
If Session.IsReadOnly Then
Message.Text = "The current Session (SessionID: " & _
Session.SessionID & ") is read-only for this page."
Else
Session("foo") = "foo"
Message.Text = "The current Session (SessionID: " & _
Session.SessionID & ") can be written to from this page."
End If
End Sub
</script>
</head>
<body>
<asp:label id="Message" runat="server"/>
</body> </html></source>
Session.Item
<source lang="csharp">
<%@ Page Language="vb" %> <html>
<head>
<script runat="server">
Sub Page_Load()
Session.Item("foo") = "foo"
Session.Item("foo2") = "foo2"
Message.Text = Session.Item("foo") & "</br>"
Message.Text &= Session.Item(1)
End Sub
</script>
</head>
<body>
<asp:label id="Message" runat="server"/>
</body> </html></source>
Session.Keys
<source lang="csharp">
<%@ Page Language="vb" %> <html>
<head>
<script runat="server">
Sub Page_Load()
Dim Key As String
Message.Text = "Session Keys:"
For Each Key in Session.Keys
Message.Text &= "</br>Key:" & Key
Message.Text &= "</br>Value:" & Session(Key)
Next
End Sub
</script>
</head>
<body>
<asp:label id="Message" runat="server"/>
</body> </html></source>
Session.LCID
<source lang="csharp">
<%@ Page Language="vb" %> <html>
<head>
<script runat="server">
Sub Page_Load()
Message.Text = "Current locale ID is: " & Session.LCID & "</br>"
Message.Text &= "Current date and time is: " & DateTime.Now() & "</br>"
Session.LCID = 1036 "France
Message.Text &= "Current locale ID is: " & Session.LCID & "</br>"
Message.Text &= "Current date and time is: " & DateTime.Now() & "</br>"
End Sub
</script>
</head>
<body>
<asp:label id="Message" runat="server"/>
</body> </html></source>
Session.Mode
<source lang="csharp">
<%@ Page Language="vb" %> <html>
<head>
<title>Session property example</title>
<script runat="server">
Sub Page_Load()
Message.Text = "Current Session State Mode: " & Session.Mode.ToString()
End Sub
</script>
</head>
<body>
<asp:label id="Message" runat="server"/>
</body> </html></source>
Session.Remove
<source lang="csharp">
<%@ Page Language="vb" %> <html>
<head>
<script runat="server">
Sub Page_Load()
If Not Session("foo") Is Nothing Then
Session.Remove("foo")
Message.Text = "Item "foo" was removed."
Else
Message.Text = "Item "foo" does not exist."
End If
End Sub
</script>
</head>
<body>
<form runat="server">
<asp:label id="Message" runat="server"/>
</form>
</body> </html></source>
Session.RemoveAll
<source lang="csharp">
<%@ Page Language="vb" %> <html>
<head>
<script runat="server">
Sub Page_Load()
If Session.Count > 0 Then
Session.RemoveAll()
Message.Text = "Session collection cleared."
Else
Message.Text = "Session collection is already empty."
End If
End Sub
</script>
</head>
<body>
<form runat="server">
<asp:label id="Message" runat="server"/>
</form>
</body> </html></source>
Session.RemoveAt
<source lang="csharp">
<%@ Page Language="vb" %> <html>
<head>
<script runat="server">
Sub Page_Load()
If Session.Count > 0 Then
Session.RemoveAt(0)
Message.Text = "The item at index 0 was removed."
Else
Message.Text = "The item at index 0 does not exist."
End If
End Sub
</script>
</head>
<body>
<form runat="server">
<asp:label id="Message" runat="server"/>
</form>
</body> </html></source>
Session.StaticObjects
<source lang="csharp">
<%@ Page Language="vb" %> <html>
<head>
<script runat="server">
Sub Page_Load()
Message.Text = "There are " & Session.StaticObjects.Count & _
" objects declared with the " & _
"<object runat="server"> syntax in Session scope."
Dim myobj As Object
For Each myObj in Session.StaticObjects
If myObj.Value.GetType.ToString() = _
"System.Web.UI.WebControls.TextBox" Then
myForm.Controls.Add(myObj.Value)
End If
Next
End Sub
</script>
</head>
<body>
<form id="myForm" runat="server">
<asp:label id="Message" runat="server"/>
</form>
</body> </html></source>
Session.Timeout
<source lang="csharp">
<%@ Page Language="vb" %> <html>
<head>
<script runat="server">
Sub Page_Load()
Message.Text = "Current Session timeout value is " & _
Session.Timeout & " minutes."
End Sub
</script>
</head>
<body>
<asp:label id="Message" runat="server"/>
</body> </html></source>
Use Session and Server.Transfer to create a wizard
<source lang="csharp">
<%@Page language="c#" runat="server" Debug="true" %> <script runat="server"> protected void Page_Load(object o, EventArgs e) {
if(IsPostBack) {
Session["theName"] = (string)theName.Text;
Server.Transfer("Default.aspx", false);
}
} </script> <form runat="server">
Name: <asp:textbox id="theName" runat="server" /> <asp:button type="submit" id="submitStep1" runat="server" Text="Go"/>
</form> File: Default.aspx
<%@Page language="c#" runat="server" %> <script runat="server"> protected void Page_Load(object o, EventArgs e) {
if(IsPostBack) {
Session["theHobby"] = theHobby.Text;
Server.Transfer("NextPage.aspx");
}
} </script> <form runat="server">
Hobby: <asp:textbox id="theHobby" runat="server"/> <asp:button type="submit" id="submitStep2" runat="server" Text="Go"/>
</form> File: NextPage.aspx <%@Page language="c#" runat="server" %> <script runat="server"> protected void Page_Load(object o, EventArgs e) {
theFinalName.Text = (string)Session["theName"]; theFinalHobby.Text = (string)Session["theHobby"];
}
</script>
<form runat="server">
Done!
Name: <asp:label id="theFinalName" runat="server" />
Hobby: <asp:label id="theFinalHobby" runat="server" />
</form></source>
