Objective-C

Nsmutablearray *sourcearray = [Nsmutablearray arraywithobjects:@ (3), @ (5), @ (7), @ (9), @ (2), @ (4), @ (8), @ (6), nil];Select sortfor (int i = 0; i {for (int j = i+1; J {Nsinteger baseidx = i;Nsinteger moveidx = j;nsnumber* basenum =

While the best objective-c coding platform So far comes from Apple, they are not just for Apple's platform. Objective-c has a long history on other platforms such as Linux, BSD and even windows. Depending on your needs, you will find some open

#import#defineOnexit\__strongvoid(^block) () __attribute__ ((Cleanup (cleanup), unused)) = ^__attribute__ ((constructor))voidExecutebefore_main () {printf ("executebefore_main\n");} __attribute__ ((destructor))voidExecuteafter_main () {printf

1, the use of random numbers 1), arc4random () more precise do not need to generate the seed immediatelyHow to use:The code for obtaining an integer between 0 and X-1 by Arc4random () is as follows:int value = Arc4random ()% x;The code to get an

Recently in the data-type app needs a good resource management tools, Excel in this respect is very good, but can first very low, the second data volume a large query is a problem.So I used Django to do a resource management gadget. The benefits are

Q: Does the fraction class apply to negative fractions? For example: Can 1/4-1/2 be displayed as-1/4?1 //--------class definition implementation refer to the previous essay, where you need to change the print method and main Main method Section------

In Objective-c, the invocation method takes a message-passing mechanism.Reference article: http://blog.csdn.net/xingyevc/article/details/39397873If a message is passed to an object, the dynamic binding mechanism of OC is used to determine the method

Definition and use of the Protocol What is an agreement?Can be used to declare a whole bunch of methods (cannot declare member variables)As long as a class follows this protocol, it is equivalent to having all the method declarations in this

Block type Block is a data type that is widely used in iOS development and is highly recommended by Apple, which functions like a function pointer in C.^ is a unique symbol of block.The implementation code for the block is included in the {}.In

What is a composite relationship? The compound relationship of a class is the most common one in the relationship of a class.A composite is a relationship with a, such as a person class that contains a member property, a book object, and

runtime abbreviation. is the system at the time of the operation of some mechanism, the most important is the message mechanism. For the C language, the function's call will decide which function to call at compile time (see here for the C-language

1. IntroductionThe knowledge of block is described in the previous article [New learn] explaining the block knowledge of objective-c. In this chapter we will take a practical example to briefly describe how block replaces proxies.2. The original

Like NSString, Nsarray, Nsdictionary is immutable, and its corresponding variable type is nsmutabledictionary. Its usage is as follows:#import@interfaceStudent:nsobject@property (nonatomic, retain) nsstring*name;+ (ID) Studentwithname: (NSString *)

#importintMainintargcConst Char*argv[]) {FILE* FP1;//define file pointers for reading files Char* FP2;//to determine if the lyrics are finished . Chars[ the];//Staging Lyrics Long intTime2=0; Long intTime=0;//used to calculate the time, the

code blockIn addition to the code in the function, the code block also includes variable bindings. The code block also has another name: Closure (closure).Code blocks protect two types of bindings: automatic and managed. Automatic binding uses

　NSDateNSDate time class, inherited from NSObject, whose object represents a point in time NSDate *date = [NSDate date]; NSLog (@ "date =%@", date);2015-12-04 19:08:00.624 ocnsdate[2955:309612] date = 2015-12-04 11:08:00 +0000Printed display

Double, float types often have unpredictable problems when you need to calculate accurately in iOS:During debugging, you can see that the Doule type D3 the value is not expected to be 9999.99 during the calculation.If important data, such as amounts,

In OC, methods are divided into class methods and instance methods.+ is a class method, which can be called directly with the class name.-For instance methods, you must use an instance of the class to invoke.@interface People:nsobject-(void) eat;+

First, the objects in OC are represented by pointers, and the invocation of the method is based on the message mechanism, = =The nature of the comparison is the address pointed to by the pointer and then the difference between isequal and

Abstract:1. Objective-c is based in SmallTalk-80, vs Simula, adopted by C + +2. Objective-c is a ' strict superset ' of C3. Objective-c model of OOP is based on Message passing to object.Detail:Objective-c 1980Object-oriented Pre-compiler