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// ==++==
//
// Copyright (c) Microsoft Corporation. All rights reserved.
//
// ==--==
/*============================================================
**
** Class: SerializationInfoEnumerator
**
**
** Purpose: A formatter-friendly mechanism for walking all of
** the data in a SerializationInfo. Follows the IEnumerator
** mechanism from Collections.
**
**
============================================================*/
namespace System.Runtime.Serialization {
using System;
using System.Collections;
using System.Diagnostics.Contracts;
//
// The tuple returned by SerializationInfoEnumerator.Current.
//
[System.Runtime.InteropServices.ComVisible(true)]
public struct SerializationEntry {
private Type m_type;
private Object m_value;
private String m_name;
public Object Value {
get {
return m_value;
}
}
public String Name {
get {
return m_name;
}
}
public Type ObjectType {
get {
return m_type;
}
}
internal SerializationEntry(String entryName, Object entryValue, Type entryType) {
m_value = entryValue;
m_name = entryName;
m_type = entryType;
}
}
//
// A simple enumerator over the values stored in the SerializationInfo.
// This does not snapshot the values, it just keeps pointers to the
// member variables of the SerializationInfo that created it.
//
[System.Runtime.InteropServices.ComVisible(true)]
public sealed class SerializationInfoEnumerator : IEnumerator {
String[] m_members;
Object[] m_data;
Type[] m_types;
int m_numItems;
int m_currItem;
bool m_current;
internal SerializationInfoEnumerator(String[] members, Object[] info, Type[] types, int numItems) {
Contract.Assert(members!=null, "[SerializationInfoEnumerator.ctor]members!=null");
Contract.Assert(info!=null, "[SerializationInfoEnumerator.ctor]info!=null");
Contract.Assert(types!=null, "[SerializationInfoEnumerator.ctor]types!=null");
Contract.Assert(numItems>=0, "[SerializationInfoEnumerator.ctor]numItems>=0");
Contract.Assert(members.Length>=numItems, "[SerializationInfoEnumerator.ctor]members.Length>=numItems");
Contract.Assert(info.Length>=numItems, "[SerializationInfoEnumerator.ctor]info.Length>=numItems");
Contract.Assert(types.Length>=numItems, "[SerializationInfoEnumerator.ctor]types.Length>=numItems");
m_members = members;
m_data = info;
m_types = types;
//The MoveNext semantic is much easier if we enforce that [0..m_numItems] are valid entries
//in the enumerator, hence we subtract 1.
m_numItems = numItems-1;
m_currItem = -1;
m_current = false;
}
public bool MoveNext() {
if (m_currItem<m_numItems) {
m_currItem++;
m_current = true;
} else {
m_current = false;
}
return m_current;
}
/// <internalonly/>
Object IEnumerator.Current { //Actually returns a SerializationEntry
get {
if (m_current==false) {
throw new InvalidOperationException(Environment.GetResourceString("InvalidOperation_EnumOpCantHappen"));
}
return (Object)(new SerializationEntry(m_members[m_currItem], m_data[m_currItem], m_types[m_currItem]));
}
}
public SerializationEntry Current { //Actually returns a SerializationEntry
get {
if (m_current==false) {
throw new InvalidOperationException(Environment.GetResourceString("InvalidOperation_EnumOpCantHappen"));
}
return (new SerializationEntry(m_members[m_currItem], m_data[m_currItem], m_types[m_currItem]));
}
}
public void Reset() {
m_currItem = -1;
m_current = false;
}
public String Name {
get {
if (m_current==false) {
throw new InvalidOperationException(Environment.GetResourceString("InvalidOperation_EnumOpCantHappen"));
}
return m_members[m_currItem];
}
}
public Object Value {
get {
if (m_current==false) {
throw new InvalidOperationException(Environment.GetResourceString("InvalidOperation_EnumOpCantHappen"));
}
return m_data[m_currItem];
}
}
public Type ObjectType {
get {
if (m_current==false) {
throw new InvalidOperationException(Environment.GetResourceString("InvalidOperation_EnumOpCantHappen"));
}
return m_types[m_currItem];
}
}
}
}
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