C / C++ / MFC

Foothill wrote:

I'm trying to dynamically resize arrays at runtime

int *x = new int[3]; // allocate room for 3 ints
x[0] = 2;
x[1] = 4;
x[2] = 6;
int *y = new int[5]; // allocate room for 5 ints
memcpy(y, x, 3 * sizeof(int)); // copy 3 ints from x to y
y[3] = 8;
y[4] = 10;
delete [] x;

Foothill wrote:

I following the exact procedures found in the MSDN article:
http://msdn.microsoft.com/en-us/library/0scy7z2d(VS.80).aspx

IntArray* A = (IntArray*)new int(sizeof num);

int *i = new int(n);

int *a = new int[n];

IntArray* A = (IntArray*)new int[num];

Foothill wrote:

#include

#include <io.h>

Foothill wrote:

int Iarray[0];

int *Iarray;

Foothill wrote:

IntArray* A = (IntArray*)new int(sizeof num);

new int

new int(5)

new int[5]

A->Iarray = new int[num];

IntArray *A = new IntArray;

IntArray A;

Foothill wrote:

for ( short i = 0 ; i < 10 ; ++i )

Foothill wrote:

cout << A->Iarray[j]," ";

cout << A->Iarray[j] << ", ";

Foothill wrote:

delete A;

delete [] A->Iarray;

struct Point
{
    double x, y;
};

struct Polyline
{
    __int32 pointCount;
    Point points[2]; // two or more
};

Stefan63 wrote:

not only hold the array of data as requested, but also additional info

void *data = GetSamples();

// Extract data
int version = * (int*) data;
unsigned int sampleCount = * (unsigned int*) (( (char*) data ) + sizeof(int))
double *samples = (double*) (( (char*) data ) + sizeof(int) + sizeof(unsigned int))

struct Samples
{
    int version;
    unsigned int sampleCount;
    double samples[];
};

void *data = GetSamples();
Samples *samples = (Samples*) data;

struct Samples
{
    int version;
    unsigned int sampleCount;
    double samples[];
};

// Calculate the size in bytes of our data block
size_t dataSizeNeeded = sizeof(int) + sizeof(unsigned int) + sizeof(double) * mySampleCount;
char *bytes = new char[dataSizeNeeded]; // Allocate enough bytes to hold the data
Samples *samples = (Samples*) bytes; // Treat it as if it was pointing to a Samples struct

samples->version = 1;
samples->sampleCount = mySampleCount;

for (size_t i = 0; i < mySampleCount; ++i)
{
    samples->samples[i] = ...;
}

// Now we have a properly initialized data block
ProcessSamples(samples);

delete [] bytes;

Niklas Lindquist wrote:

If one could design it all from the beginning, this would never have been discussed.

stephen_young wrote:

in CAppEx::InitInstance(),but there were nothing happaned.I