OC基础语法学习：Foundation框架

常用结构体：

在Foundation中定义了很多常用结构体类型来简化我们的日常开发，这些结构体完全采用Objective-C定义，和我们自己定义的结构体没有任何区别，之所以由框架为我们提供完全是为了简化我们的开发。常用的结构体有NSRange、NSPoint、NSSize、NSRect等

#import <Foundation/Foundation.h>/*NSRange表示一个范围*/void test1(){    NSRange rg={3,5};//第一参数是起始位置第二个参数是长度    //NSRange rg;    //rg.location=3;    //rg.length=5;    //NSRange rg={.location=3,.length=5};    //常用下面的方式定义 NSRange rg2=NSMakeRange(3,5);//使用NSMakeRange定义一个NSRange     //打印NSRange可以使用Foundation中方法 NSLog(@"rg2 is %@", NSStringFromRange(rg2));//注意不能直接NSLog(@"rg2 is %@", rg2)，因为rg2不是对象（准确的说%@是指针）而是结构体}/*NSPoint表示一个点*/void test2(){    NSPoint p=NSMakePoint(10, 15);//NSPoint其实就是CGPoint    //这种方式比较常见 NSPoint p2=CGPointMake(10, 15);    NSLog(NSStringFromPoint(p2));}/*NSSize表示大小*/void test3(){    NSSize s=NSMakeSize(10, 15);//NSSize其实就是CGSize    //这种方式比较常见 CGSize s2=CGSizeMake(10, 15);    NSLog(NSStringFromSize(s2));}/*NSRect表示一个矩形*/void test4(){    NSRect r=NSMakeRect(10, 5, 100, 200);//NSRect其实就是CGRect    //这种方式比较常见 NSRect r2=CGRectMake(10, 5, 100, 200);    NSLog(NSStringFromRect(r2));}int main(int argc, const char * argv[]) {    @autoreleasepool {        test1();        test2();        test3();        test4();    } return 0;}

不可变数组

////  main.m//  FoundationFramework////  Created by Kenshin Cui on 14-2-16.//  Copyright (c) 2014年 Kenshin Cui. All rights reserved.//#import <Foundation/Foundation.h>#import "Person.h"void test1(){    //NSArray长度不可变所以初始化的时候就赋值，并且最后以nil结尾    //此外需要注意NSArray不能存放C语言的基础类型    NSObject *obj=[[NSObject alloc]init];    //NSArray *array1=[[NSArray alloc] initWithObjects:@"abc",obj,@"cde",@"opq", nil];    NSArray *array1=[NSArray arrayWithObjects:@"abc",obj,@"cde",@"opq",@25, nil];    NSLog(@"%zi",array1.count);//数组长度,结果：5    NSLog(@"%i",[array1 containsObject:@"cde"]);//是否包含某个对象，结果：1    NSLog(@"%@",[array1 lastObject]);//最后一个对象，结果：25    NSLog(@"%zi",[array1 indexOfObject:@"abc"]);//对象所在的位置：0    Person *person1=[Person personWithName:@"Kenshin"];    Person *person2=[Person personWithName:@"Kaoru"];    Person *person3=[Person personWithName:@"Rosa"];    NSArray *array2=[[NSArray alloc]initWithObjects:person1,person2,person3, nil];    [array2 makeObjectsPerformSelector:@selector(showMessage:) withObject:@"Hello,world!"];//执行所有元素的showMessage方法,后面的参数最多只能有一个    /*结果：     My name is Kenshin,the infomation is "Hello,world!".     My name is Kaoru,the infomation is "Hello,world!".     My name is Rosa,the infomation is "Hello,world!".     */}//数组的遍历void test2(){    NSObject *obj=[[NSObject alloc]init];    NSArray *array=[[NSArray alloc] initWithObjects:@"abc",obj,@"cde",@"opq",@25, nil];    //方法1    for(int i=0,len=array.count;i<len;++i){        NSLog(@"method1:index %i is %@",i,[array objectAtIndex:i]);    }    /*结果：     method1:index 0 is abc     method1:index 1 is <NSObject: 0x100106de0>     method1:index 2 is cde     method1:index 3 is opq     method1:index 4 is 25     */    //方法2    for(id obj in array){        NSLog(@"method2:index %zi is %@",[array indexOfObject:obj],obj);    }    /*结果：     method2:index 0 is abc     method2:index 1 is <NSObject: 0x100602f00>     method2:index 2 is cde     method2:index 3 is opq     method2:index 4 is 25     */    //方法3,利用代码块方法    [array enumerateObjectsUsingBlock:^(id obj, NSUInteger idx, BOOL *stop) {        NSLog(@"method3:index %zi is %@",idx,obj);        if(idx==2){//当idx=2时设置*stop为YES停止遍历            *stop=YES;        }    }];    /*结果：     method3:index 0 is abc     method3:index 1 is <NSObject: 0x100106de0>     method3:index 2 is cde     */    //方法4，利用迭代器    //NSEnumerator *enumerator= [array objectEnumerator];//获得一个迭代器    NSEnumerator *enumerator=[array reverseObjectEnumerator];//获取一个反向迭代器    //NSLog(@"all:%@",[enumerator allObjects]);//获取所有迭代对象，注意调用完此方法迭代器就遍历完了，下面的nextObject就没有值了    id obj2=nil;    while (obj2=[enumerator nextObject]) {        NSLog(@"method4:%@",obj2);    }    /*结果：     method4:25     method4:opq     method4:cde     method4:<NSObject: 0x100106de0>     method4:abc     */}//数组派生出新的数组void test3(){    NSArray *array=[NSArray arrayWithObjects:@"1",@"2",@"3", nil];    NSArray *array2=[array arrayByAddingObject:@"4"];//注意此时array并没有变    NSLog(@"%@",array2);    /*结果：     (         1,         2,         3,         4     )     */    NSLog(@"%@",[array2 arrayByAddingObjectsFromArray:[NSArray arrayWithObjects:@"5",@"6", nil]]);//追加形成新的数组    /*结果：     (         1,         2,         3,         4,         5,         6     )     */    NSLog(@"%@",[array2 subarrayWithRange:NSMakeRange(1, 3)]);//根据一定范围取得生成一个新的数组    /*结果：     (         2,         3,         4     )     */    NSLog(@"%@",[array componentsJoinedByString:@","]);//数组连接，形成一个字符串    //结果：1,2,3    //读写文件    NSString *path=@"/Users/KenshinCui/Desktop/array.xml";    [array writeToFile:path atomically:YES];    NSArray *array3=[NSArray arrayWithContentsOfFile:path];    NSLog(@"%@",array3);    /*结果：     (         1,         2,         3     )     */}//数组排序void test4(){    //方法1,使用自带的比较器    NSArray *array=[NSArray arrayWithObjects:@"3",@"1",@"2", nil];    NSArray *array2= [array sortedArrayUsingSelector:@selector(compare:)];    NSLog(@"%@",array2);    /*结果：     (         1,         2,         3     )     */    //方法2,自己定义比较器    Person *person1=[Person personWithName:@"Kenshin"];    Person *person2=[Person personWithName:@"Kaoru"];    Person *person3=[Person personWithName:@"Rosa"];    NSArray *array3=[NSArray arrayWithObjects:person1,person2,person3, nil];    NSArray *array4=[array3 sortedArrayUsingSelector:@selector(comparePerson:)];    NSLog(@"%@",array4);    /*结果：     (         "name=Kaoru",         "name=Kenshin",         "name=Rosa"     )     */    //方法3使用代码块    NSArray *array5=[array3 sortedArrayUsingComparator:^NSComparisonResult(Person *obj1, Person *obj2) {        return [obj2.name compare:obj1.name];//降序    }];    NSLog(@"%@",array5);    /*结果：     (         "name=Rosa",         "name=Kenshin",         "name=Kaoru"     )     */    //方法4 通过描述器定义排序规则    Person *person4=[Person personWithName:@"Jack"];    Person *person5=[Person personWithName:@"Jerry"];    Person *person6=[Person personWithName:@"Tom"];    Person *person7=[Person personWithName:@"Terry"];    NSArray *array6=[NSArray arrayWithObjects:person4,person5,person6,person7, nil];    //定义一个排序描述    NSSortDescriptor *personName=[NSSortDescriptor sortDescriptorWithKey:@"name" ascending:YES];    NSSortDescriptor *accountBalance=[NSSortDescriptor sortDescriptorWithKey:@"account.balance" ascending:YES];    NSArray *des=[NSArray arrayWithObjects:personName,accountBalance, nil];//先按照person的name排序再按照account的balance排序    NSArray *array7=[array6 sortedArrayUsingDescriptors:des];    NSLog(@"%@",array7);    /*结果：     (         "name=Jack",         "name=Jerry",         "name=Terry",         "name=Tom"     )     */}int main(int argc, const char * argv[]) {    test1();    test2();    test3();    test4();    return 0;}

可变数组

#import <Foundation/Foundation.h>#import "Person.h"void test1(){    Person *person1=[Person personWithName:@"Kenshin"];    Person *person2=[Person personWithName:@"Kaoru"];    Person *person3=[Person personWithName:@"Rosa"];    NSMutableArray *array1=[NSMutableArray arrayWithObjects:person1,person2,person3, nil];    NSLog(@"%@",array1);    /*结果：     (         "name=Kenshin",         "name=Kaoru",         "name=Rosa"     )     */    Person *person4=[Person personWithName:@"Jack"];//此时person4的retainCount为1    [array1 addObject:person4];//添加一个元素,此时person4的retainCount为2    NSLog(@"%@",array1);    /*结果：     (         "name=Kenshin",         "name=Kaoru",         "name=Rosa",         "name=Jack"     )     */    [array1 removeObject:person3];//删除一个元素    NSLog(@"%@",array1);    /*结果：     (         "name=Kenshin",         "name=Kaoru",         "name=Jack"     )     */    [array1 removeLastObject];//删除最后一个元素,//此时person4的retainCount为1    NSLog(@"%@",array1);    /*结果：     (         "name=Kenshin",         "name=Kaoru"     )     */    [array1 removeAllObjects];//删除所以元素    //注意当往数组中添加一个元素时会retain因此计数器+1，当从数组中移除一个元素时会release因此计数器-1    //当NSMutalbeArray对象release的时候会依次调用每一个对象的release}void test2(){    NSMutableArray *array1=[NSMutableArray arrayWithObjects:@"1",@"3",@"2", nil];    NSLog(@"%@",array1);    /*结果：     (         1,         3,         2     )     */    NSArray *array2= [array1 sortedArrayUsingSelector:@selector(compare:)];//注意这个方法没有修改array1    NSLog(@"%@",array1);    /*结果：     (         1,         3,         2     )     */    NSLog(@"%@",array2);    /*结果：     (         1,         2,         3     )     */    [array1 sortUsingSelector:@selector(compare:)];//这个方法会修改array1    NSLog(@"%@",array1);    /*结果：     (         1,         2,         3     )     */}int main(int argc, const char * argv[]) {    test1();    test2();    return 0;}