IPhone development tips

1: In iPhone memory management, when malloc is used to allocate memory on the heap, the corresponding free heap memory should be used instead of the release-related objects. The following code:

@ Interface MemoryTestProjViewController: UIViewController {

@ Public

NSMutableArray * memoryArray;

}

 

@ End

 

@ Interface MemoryTestProjItem: NSObject

{

@ Public

Char * innerItem;

}

@ End

 

During initialization, The innerItem pointer allocates memory on the heap space, but remember to call the free function to release the heap space. The Code is as follows:

-(Void) viewDidUnload {

// Release any retained subviews of the main view.

// E.g. self. myOutlet = nil;

 

MemoryArray = [[NSMutableArray alloc] initWithCapacity: 10];

 

For (int I = 0; I <1024; I ++)

{

MemoryTestProjItem * item = [[MemoryTestProjItem alloc] init];

Item-& gt; innerItem = (char *) malloc (1024 );

[MemoryArray addObject: item];

[Item release];

Free (item-> innerItem );

Free (item );

}

[MemoryArray removeAllObjects];

}

II: If CFHTTPMessageRef is used for HTTP Communication Development in the iPhone, Content-Length Content is not included in the default header, and the display settings are required. The Code is as follows:

NSString * contentLen = [[NSString alloc] initWithFormat "% d", [bodyData length];

CFHTTPMessageSetHeaderFieldValue (myRequest,

CFSTR ("Content-Length"), (CFStringRef) contentLen );

CFDataRef mySerializedRequest = CFHTTPMessageCopySerializedMessage (myRequest); // serialize the request

The above code is worth noting that CFSTR is a macro in the iPhone and cannot dynamically set the Content-Length for it. For example, the following code cannot be compiled:

CFHTTPMessageSetHeaderFieldValue (myRequest,

CFSTR ("Content-Length"), CFSTR ([contentLen UTF8String]);