public static unsafe MyStruct *Allocate(MyStruct MyStruct)
{
MyStruct *MyStructHandlerPointer = (MyStruct *)Marshal.AllocHGlobal(sizeof(MyStruct));
*MyStructHandlerPointer = MyStruct;
return(MyStructHandlerPointer);
}
/// <summary>
/// 引用类型的指针
/// </summary>
public static void Demo2()
{
//结构指针
MyStruct aStruct = new MyStruct();
MyStruct *pStruct = &aStruct;
(*pStruct).F = 3.4F;
(*pStruct).x = 11;
pStruct->F = 3.5F;
pStruct->x = 2;
long *pLong = &(pStruct->x);
//类成员指针
Test myClass = new Test();
/*//会产生编码错误，以下写法
* long* pLong1 = &(myClass.X);*/
fixed(float *pFloat1 = &(myClass.F))
fixed(long *pLong1 = &(myClass.X))
{
}
}
static void Main(string[] args)
{
MyStruct mc = new MyStruct(10);
// Will print 10
Console.WriteLine(mc.i);
unsafe
{
MyStruct *pmc = &mc;
// Will print the address of mc
Console.WriteLine((IntPtr)pmc);
}
// Assign to mc
mc = new MyStruct(20);
// Will print 20; mc was modified
Console.WriteLine(mc.i);
unsafe
{
MyStruct *p = &mc;
// Will print the same address as above.
// mc was modified in place
// because structs have value semantics
Console.WriteLine((IntPtr)p);
}
}
unsafe static void Main(string[] args)
{
MyStruct ms; //Not necessary to instantiate aan instance of a struct with new keyword
MyStruct *ms1 = &ms;
ms1->SetXY(10, 20);
ms1->ShowXY();
}
static void unsafe Main(string[] args)
{
int x = 10;
int * ptr1 = &x;
int y = *ptr1;
MyStruct st = new MyStruct();
MyStruct *ptrst = &st;
ptrstr->a();
}
static void Main()
{
MyClass o = new MyClass();
MyStruct s = new MyStruct();
unsafe
{
fixed(int *p = &o.fld1, q = &o.fld2)
{
* p = 0;
* q = 0;
MyStruct *r = &s;
(*r).fld = 0;
}
}
int[] arr = { 1, 2, 3 };
addone(arr);
}
private void Start()
{
using (UnsafeListV2 <MyStruct> warmList = new UnsafeListV2 <MyStruct>(1, 1))
{
MyStruct *MyStructPtr = MyStruct.Allocate(new MyStruct(1, true, 5));
warmList.Add(MyStructPtr);
Marshal.FreeHGlobal((IntPtr)MyStructPtr);
}
Profiler.BeginSample("UnsafeTest : Allocation");
var list = new UnsafeListV2 <MyStruct>(1024, 2);
for (int i = 0; i < 1024; i++)
{
MyStruct *MyStructPtrTmp = MyStruct.Allocate(new MyStruct(1, true, 5));
list.Add(MyStructPtrTmp);
}
Profiler.EndSample();
Profiler.BeginSample("UnsafeTest : DeAlloc");
for (int i = 0; i < 1000; i++)
{
var foundPtr = list.Get(i);
if ((IntPtr)foundPtr != IntPtr.Zero)
{
Marshal.FreeHGlobal((IntPtr)foundPtr);
}
}
list.Dispose();
Profiler.EndSample();
}
