NSArray和NSMutableArray的常用方法
/* 初始化方法: 1.init返回一個空數組 2.initWithArray從已有數組初始化 3.initWithContentsOfFile//從plist文件加載 4.initWithContentsOfUrl//從網絡地址上獲取 5.initWithObject用一個對象初始化 6.initWithObjects從多對象初始化self.theDataArray=[[NSMutableArray alloc]initWithCapacity:5];//指定有五個元素初始化 */ /*打印第一個元素: NSLog(@"the object is:%@",[theDataArray firstObjectCommonWithArray:theDataArray]);
/ /打印最后一個元素: NSLog(@"the object is:%@",[theDataArray lastObject]); / /枚舉所有元素,方法一: for (NSString theStr in theDataArray) { NSLog(@"%@:",theStr); } / /枚舉所有元素,方法二: for (int i=0,i<[theDataArray count],i++) { //NSLog(@"%@:",[theDataArray objectAtIndex:i]); } / / 枚舉所有元素,方法三,用枚舉器: NSEnumerator enumerator=[theDataArray objectEnumerator]; id obj; while (obj =[enumerator nextObject]) { NSLog(@"%@",obj); } */
/* //添加元素 [theDataArray addObject:@"這是新添加的元素"];//從最后開始添加 */ /* //從指定索引插入元素 [theDataArray insertObject:@"this is inerted object" atIndex:0];//是插入到指定 索引的前面 */ /* //修改.更新元素 [theDataArray replaceObjectAtIndex:0 withObject:@"new obj"];//指定索引修改 */ /* //判斷數組是否包含某個對象 if ([theDataArray containsObject:@"selectiont"]) { NSLog(@"the object selection is contained in array"); } else{ NSLog(@"not contain"); } */ /* //獲取元素索引 NSLog(@"the idx is:%i",[theDataArray indexOfObject:@"selection"]); */ /*//數組元素排序 方法一:
NSArray theTempArr=[[NSArray alloc] initWithArray:[theDataArray sortedArrayUsingSelector:@selector(caseInsensitiveCompare:)]]; / //[theDataArray sortedArrayUsingSelector:@selector(caseInsensitiveCompare:)]; // or @selector(compare:)
/*//數組元素排序 方法二:
NSLog(@"before sorted array:%@",theDataArray); NSCountedSet *cset=[[NSCountedSet alloc] initWithArray:theDataArray]; NSArray *theTempArr=[[NSArray alloc] initWithArray:[[cset allObjects]sortedArrayUsingSelector:@selector(compare:)]]; NSLog(@"after sorted array:%@",theTempArr); */
/ //對數組對象進行排序 NSSortDescriptor NSSortDescriptor sortDescriptor=[[NSSortDescriptor alloc] initWithKey:@"name" ascending:YES];//@“name”是對象屬性 [theDataArray sortUsingDescriptors:[NSArray arrayWithObject:sortDescriptor]];//返回排序好的數組
//還可以用自定義方法:[theDataArray sortUsingSelector:@selector(custom Method:)]; -(NSInteger)customMethod:(someObject )otherObj{ NSCompareResult compareResult=[self.name compare:otherObj.name]; if(compareResult == NSOrderedSame) return 0; if(compareResult == NSOrderedAscending) return 1; else return -1; }/
/ //對象數組過濾(NSPredicate) NSArray keyArray=[[NSArray alloce]initWtihObjects:@"A",@"B",nil]; for (NSString *key in keyArray) { //定義規則:
NSPredicate apredicate=[NSPredicate predicateWithFormat:@"SELF.name beginswith[c] %@",key]; //SELF.name是對象屬性,beginswith[c] %@",key 表示選出name以key開頭的對象 //或者 : NSPredicate apredicate=[NSPredicate predicateWithFormat:@"SELF.name contains [c] %@",key]; //contains[c]
%@",key 表示選出name中包含有key的對象 //或者 : NSInteger age=20; NSPredicate *apredicate=[NSPredicate predicateWithFormat:@"SELF.age > %i",age]; // 表示選出age>20的對象//或者 : NSString matchStr=@"hel"; NSPredicate *apredicate=[NSPredicate predicateWithFormat:@"SELF.name like %@",matchStr]; // 表示選出name中包含與字符串matchStr相似的對象
NSArray *newArr=[theDataArray filteredArrayUsingPredicate:apredicate]; [theDataDict setValue:newArr forKey:key]; }
*/
/ //刪除數組元素 NSMutableArray tempArray=[[NSMutableArray alloc]initWithObjects:@"one",@"tow",@"threr",nil]; [tempArray removeObjectAtIndex:0];//從指定索引移除 [tempArray removeAllObjects];//移除所有元素 [tempArray removeLastObject];//移除最后那個元素 [tempArray removeObjectsInArray:newArray];//移除指定數組中元素 [tempArray removeObjectsAtIndexes: NSIndexSet *__strong)];//從所選擇的索引中移除
*/</pre>