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// ==++==
//
// Copyright (c) Microsoft Corporation. All rights reserved.
//
// ==--==
/*============================================================
**
** Class: ValueType
**
**
** Purpose: Base class for all value classes.
**
**
===========================================================*/
namespace System {
using System;
using System.Reflection;
using System.Runtime.CompilerServices;
using System.Runtime.Versioning;
[Serializable]
[System.Runtime.InteropServices.ComVisible(true)]
public abstract class ValueType {
[System.Security.SecuritySafeCritical]
public override bool Equals (Object obj) {
BCLDebug.Perf(false, "ValueType::Equals is not fast. "+this.GetType().FullName+" should override Equals(Object)");
if (null==obj) {
return false;
}
RuntimeType thisType = (RuntimeType)this.GetType();
RuntimeType thatType = (RuntimeType)obj.GetType();
if (thatType!=thisType) {
return false;
}
Object thisObj = (Object)this;
Object thisResult, thatResult;
// if there are no GC references in this object we can avoid reflection
// and do a fast memcmp
if (CanCompareBits(this))
return FastEqualsCheck(thisObj, obj);
FieldInfo[] thisFields = thisType.GetFields(BindingFlags.Instance | BindingFlags.Public | BindingFlags.NonPublic);
for (int i=0; i<thisFields.Length; i++) {
thisResult = ((RtFieldInfo)thisFields[i]).UnsafeGetValue(thisObj);
thatResult = ((RtFieldInfo)thisFields[i]).UnsafeGetValue(obj);
if (thisResult == null) {
if (thatResult != null)
return false;
}
else
if (!thisResult.Equals(thatResult)) {
return false;
}
}
return true;
}
[System.Security.SecuritySafeCritical] // auto-generated
[ResourceExposure(ResourceScope.None)]
[MethodImplAttribute(MethodImplOptions.InternalCall)]
private static extern bool CanCompareBits(Object obj);
[System.Security.SecuritySafeCritical] // auto-generated
[ResourceExposure(ResourceScope.None)]
[MethodImplAttribute(MethodImplOptions.InternalCall)]
private static extern bool FastEqualsCheck(Object a, Object b);
/*=================================GetHashCode==================================
**Action: Our algorithm for returning the hashcode is a little bit complex. We look
** for the first non-static field and get it's hashcode. If the type has no
** non-static fields, we return the hashcode of the type. We can't take the
** hashcode of a static member because if that member is of the same type as
** the original type, we'll end up in an infinite loop.
**Returns: The hashcode for the type.
**Arguments: None.
**Exceptions: None.
==============================================================================*/
[System.Security.SecuritySafeCritical] // auto-generated
[ResourceExposure(ResourceScope.None)]
[MethodImplAttribute(MethodImplOptions.InternalCall)]
public extern override int GetHashCode();
[MethodImplAttribute(MethodImplOptions.InternalCall)]
internal static extern int GetHashCodeOfPtr(IntPtr ptr);
public override String ToString()
{
return this.GetType().ToString();
}
}
}
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