Objective-C中NSArray和NSMutableArray的基本用法

/*---------------------NSArray---------------------------*///创建数组NSArray *array1 = [NSArray arrayWithObject:@"1"];NSArray *array2 = [NSArray arrayWithObjects:@"1",@"2",@"3",nil];NSArray *array3 = [NSArray arrayWithArray:array2];NSLog(@"array1 = %@",array1);NSLog(@"array2 = %@",array2);NSLog(@"array3 = %@",array3);//获取数组内数据个数int count = [array2 count];NSLog(@"array2 size is %d",count);//访问数组内的数据NSString *str1 = [array2 objectAtIndex:0];NSLog(@"array2 first content is %@",str1);//数组中插入数据   返回新的数组NSArray *array4 = [array3 arrayByAddingObject:@"4"];NSLog(@"array4 = %@",array4);//数组内的数据以制定字符连接NSString *str2 = [array4 componentsJoinedByString:@","];NSLog(@"str2 = %@",str2);//判断数组中是否包含某对象BOOL b1 = [array4 containsObject:@"4"];BOOL b2 = [array4 containsObject:@"5"];NSLog(@"b1 = %d,b2 = %d",b1,b2);//取数组内制定对象的索引int index = [array4 indexOfObject:@"4"];NSLog(@"index = %d",index);NSString *str3 = [array4 lastObject];NSLog(@"array4 last object is %@",str3);/*-----------------------可变数组NSMutableArray-----------------------------------------*///定义一个空的数组NSMutableArray *mArray2 = [[NSMutableArray alloc]init];//初始化数组 指定数组长度   但可变NSMutableArray *mArray1 = [NSMutableArray arrayWithCapacity:5];//向数组中添加元素[mArray1 addObject:@"aaaa"];[mArray1 addObject:@"cccc"];NSLog(@"mArray1 = %@",mArray1);//向指定位置插入元素[mArray1 insertObject:@"bbbb" atIndex:1];[mArray1 insertObject:@"dddd" atIndex:[mArray1 count]];[mArray1 insertObject:@"eeee" atIndex:[mArray1 count]];NSLog(@"mArray1 = %@",mArray1);//移除元素[mArray1 removeObject:@"eeee"];NSLog(@"mArray1 = %@",mArray1);[mArray1 removeObjectAtIndex:[mArray1 count]-1];NSLog(@"mArray1 = %@",mArray1);NSArray *array5 = [NSArray arrayWithObjects:@"bbbb",@"cccc",nil];[mArray1 removeObjectsInArray:array5];NSLog(@"mArray1 = %@",mArray1);//向数组内插入数组NSMutableArray *mArray2 = [NSMutableArray arrayWithObjects:@"aaaa",@"aaaa",nil];[mArray2 addObject:@"bbbb"];NSLog(@"mArray2 = %@",mArray2);[mArray2 addObjectsFromArray:array4];NSLog(@"mArray2 = %@",mArray2);//替换元素[mArray2 replaceObjectAtIndex:[mArray2 count]-1 withObject:@"5"];NSLog(@"mArray2 = %@",mArray2);//遍历数组  常规方法:性能较低NSArray *array6 = [NSArray arrayWithObjects:@"a",@"b",@"c",@"d",@"e",nil];int len = [array6 count];for (int i=0; i<len; i++) {    NSString *value = [array6 objectAtIndex:i];    NSLog(@"array6 %d content is %@",i,value);}//枚举遍历  相当于java中的增强for循环for (NSString *string in array6) {    NSLog(@"array6 content is %@",string);}NSLog(@"-----------------------");//当不确定数组元素类型时for(id string in array6){    NSLog(@"array6 content is %@",string);}