1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
|
//------------------------------------------------------------------------------
// <copyright file="SessionPageStatePersister.cs" company="Microsoft">
// Copyright (c) Microsoft Corporation. All rights reserved.
// </copyright>
//------------------------------------------------------------------------------
namespace System.Web.UI {
using System.Collections;
using System.Collections.Specialized;
using System.IO;
using System.Text;
using System.Web.SessionState;
using System.Web.Configuration;
using System.Web.Security.Cryptography;
public class SessionPageStatePersister : PageStatePersister {
private const string _viewStateSessionKey = "__SESSIONVIEWSTATE";
private const string _viewStateQueueKey = "__VIEWSTATEQUEUE";
public SessionPageStatePersister(Page page) : base (page) {
HttpSessionState session = null;
try {
session = page.Session;
}
catch {
// ignore, throw if session is null.
}
if (session == null) {
throw new ArgumentException(SR.GetString(SR.SessionPageStatePersister_SessionMustBeEnabled));
}
}
public override void Load() {
NameValueCollection requestValueCollection = Page.RequestValueCollection;
if (requestValueCollection == null) {
return;
}
try {
string combinedSerializedStateString = Page.RequestViewStateString;
string persistedStateID = null;
bool controlStateInSession = false;
// SessionState will persist a Pair of <bool requiresControlStateInSession, string/pair>,
// where if requiresControlStateInSession is true, second will just be the sessionID, as
// we will store both control state and view state in session. Otherwise, we store just the
// view state in session and the pair will be <id, ControlState>
if (!String.IsNullOrEmpty(combinedSerializedStateString)) {
Pair combinedState = (Pair)Util.DeserializeWithAssert(StateFormatter2, combinedSerializedStateString, Purpose.WebForms_SessionPageStatePersister_ClientState);
// Check if we are storing control state in session as well
if ((bool)combinedState.First) {
// So the second is the persistedID
persistedStateID = (string)combinedState.Second;
controlStateInSession = true;
}
else {
// Second is <sessionID, ControlState>
Pair pair = (Pair)combinedState.Second;
persistedStateID = (string)pair.First;
ControlState = pair.Second;
}
}
if (persistedStateID != null) {
object sessionData = Page.Session[_viewStateSessionKey + persistedStateID];
if (controlStateInSession) {
Pair combinedState = sessionData as Pair;
if (combinedState != null) {
ViewState = combinedState.First;
ControlState = combinedState.Second;
}
}
else {
ViewState = sessionData;
}
}
}
catch (Exception e) {
// Setup the formatter for this exception, to make sure this message shows up
// in an error page as opposed to the inner-most exception's message.
HttpException newException = new HttpException(SR.GetString(SR.Invalid_ControlState), e);
newException.SetFormatter(new UseLastUnhandledErrorFormatter(newException));
throw newException;
}
}
/// <devdoc>
/// To be supplied.
/// </devdoc>
public override void Save() {
bool requiresControlStateInSession = false;
object clientData = null;
Triplet vsTrip = ViewState as Triplet;
// no session view state to store.
if ((ControlState != null) ||
((vsTrip == null || vsTrip.Second != null || vsTrip.Third != null) && ViewState != null)) {
HttpSessionState session = Page.Session;
string sessionViewStateID = Convert.ToString(DateTime.Now.Ticks, 16);
object state = null;
requiresControlStateInSession = Page.Request.Browser.RequiresControlStateInSession;
if (requiresControlStateInSession) {
// ClientState will just be sessionID
state = new Pair(ViewState, ControlState);
clientData = sessionViewStateID;
}
else {
// ClientState will be a <sessionID, ControlState>
state = ViewState;
clientData = new Pair(sessionViewStateID, ControlState);
}
string sessionKey = _viewStateSessionKey + sessionViewStateID;
session[sessionKey] = state;
Queue queue = session[_viewStateQueueKey] as Queue;
if (queue == null) {
queue = new Queue();
session[_viewStateQueueKey] = queue;
}
queue.Enqueue(sessionKey);
SessionPageStateSection cfg = RuntimeConfig.GetConfig(Page.Request.Context).SessionPageState;
int queueCount = queue.Count;
if (cfg != null && queueCount > cfg.HistorySize ||
cfg == null && queueCount > SessionPageStateSection.DefaultHistorySize) {
string oldSessionKey = (string)queue.Dequeue();
session.Remove(oldSessionKey);
}
}
if (clientData != null) {
Page.ClientState = Util.SerializeWithAssert(StateFormatter2, new Pair(requiresControlStateInSession, clientData), Purpose.WebForms_SessionPageStatePersister_ClientState);
}
}
}
}
|
