Arrays in Scala are generally immutable, so we need to create a new array that will store the concatenated array in Scala. Or another method could be creating mutable arrays that will save memory. For merging two arrays Scala provides you multiple methods and we will discuss them one by one...
NSLog(@"str_mutable1 : %@, str_mutable2 : %", str_mutable1, str_2); //复制不可变字符串 NSString * str1 = [str copy]; NSMutableString * str2 = [str_mutable copy]; [str2 appendString:@" mutable"]; NSLog(@"str_mutable2 : %@", str_mutable2); } return 0; } -- 执行...
定义谓词:使用 NSPredicate 的format 方法定义一个条件表达式。在这个例子中,我们使用了 CONTAINS[c] 操作符来检查字符串是否包含子字符串 "an"。 应用谓词:使用 filtered(using:) 方法将谓词应用于数组,返回一个新的过滤后的数组。 参考链接 Apple Developer Documentation - NSPredicate 通过以上步骤和示例代码,你...
newArray = (NSMutableArray*)CFPropertyListCreateDeepCopy(kCFAllocatorDefault, (CFPropertyListRef)oldArray, kCFPropertyListMutableContainers); NSLog(@"newArray:%@", newArray); ===NSMutableArray===(可变数组) Mutable version of NSArray. - (void)addObject:(id)anObject; // 在array最后添加anObjec...
将数组中内容拷贝到Buffer内(使用改方法需要先导包:import scala.collection.mutable.ArrayBuffer) val a=Array(1,2,3) val b=newArrayBuffer[Int]() a.copyToBuffer(b)//scala.collection.mutable.ArrayBuffer[Int] = ArrayBuffer(1, 2, 3) def corresponds(that:GenSeq)(p=>boolean):boolean ...
When the destination array’s element type is a class or an@objcprotocol, bridging fromNSArraytoArrayfirst calls thecopy(with:)(- copyWithZone:in Objective-C) method on the array to get an immutable copy and then performs additional Swift bookkeeping work that takes O(1) time. For instan...
The function expects a pointer to an array of signed integers as well as the length of the array. The second argument is necessary because C doesn’t keep track of the number of elements in arrays. Then, the function loops over array indices and increments each element by one....
Scala中的Array操作 定长(scala.collection.immutable.Array)的概念:一经声明,长度不能改变 变长(scala.collection.mutable.ArrayBuffer)的概念:声明之后,长度可变(可以追加新元素) take取出前n项元素,并返回到一个新数组 takeRight取出后n项元素,并返回到一个新数组 drop删除前n项,将剩余元素返回到新数组... ...
data = bytes(b"abc") for value in data: print(value) print() # Create bytearray from byte literal. arr = bytearray(b"abc") for value in arr: print(value) 97 98 99 97 98 99 Slice, bytearray. We can slice bytearrays. And because bytearray is mutable, we can use slices to ch...
or removed from it. Once the array and its elements are created, you can no longer add or remove any elemetns. You can, however, change the values of elements in the array. This is in contrast to a vector array, which is a mutable array, in which elements can be added or removed....