Int8Array

Int8Array 类型数组表示二进制补码8位有符号整数的数组。内容初始化为0。一旦建立,你可以使用对象的方法引用数组中的元素,或使用标准数组索引语法(即,使用括号注释)。

语法

new Int8Array(length);
new Int8Array(typedArray);
new Int8Array(object);
new Int8Array(buffer [, byteOffset [, length]]);

有关构造函数语法和参数的更多信息,请访问 TypedArray .

属性

Int8Array.BYTES_PER_ELEMENT
返回数组中每个元素的大小.在 Int8Array中这个值为1 .
Int8Array.length
此属性为固定值属性,值为3.查看 Int8Array.prototype.length 获得获取数组内元素个数方法。
Int8Array.name
返回构造器方法名称.在Int8Array类型中此值为"Int8Array"。
Int8Array.prototype
TypedArray 对象的构造原型。

方法

Int8Array.from()
从类数组对象或迭代器生成int8Array数组对象.参照 Array.from() .
Int8Array.of()
以多个参数构造Int8Array对象,参照 Array.of() .

Int8Array 原型方法

所有 Int8Array 对象都继承自 %TypedArray%.prototype .

属性

Int8Array.prototype.constructor
这个方法会返回对象的构造原型.默认为 Int8Array构造函数 .
Int8Array.prototype.buffer 只读
Returns the ArrayBuffer referenced by the Int8Array Fixed at construction time and thus read only .
Int8Array.prototype.byteLength 只读
Returns the length(in bytes)of the Int8Array from the start of its ArrayBuffer . Fixed at construction time and thus read only.
Int8Array.prototype.byteOffset 只读
Returns the offset(in bytes)of the Int8Array from the start of its ArrayBuffer . Fixed at construction time and thus read only.
Int8Array.prototype.length 只读
Returns the number of elements hold in the Int8Array . Fixed at construction time and thus read only.

方法

Int8Array.prototype.copyWithin()
Copies a sequence of array elements within the array. See also Array.prototype.copyWithin() .
Int8Array.prototype.entries()
Returns a new Array Iterator object that contains the key/value pairs for each index in the array. See also Array.prototype.entries() .
Int8Array.prototype.every()
Tests whether all elements in the array pass the test provided by a function. See also Array.prototype.every() .
Int8Array.prototype.fill()
Fills all the elements of an array from a start index to an end index with a static value. See also Array.prototype.fill() .
Int8Array.prototype.filter()
Creates a new array with all of the elements of this array for which the provided filtering function returns true. See also Array.prototype.filter() .
Int8Array.prototype.find()
Returns the found value in the array, if an element in the array satisfies the provided testing function or undefined if not found. See also Array.prototype.find() .
Int8Array.prototype.findIndex()
Returns the found index in the array, if an element in the array satisfies the provided testing function or -1 if not found. See also Array.prototype.findIndex() .
Int8Array.prototype.forEach()
Calls a function for each element in the array. See also Array.prototype.forEach() .
Int8Array.prototype.includes()
Determines whether a typed array includes a certain element, returning true or false as appropriate. See also Array.prototype.includes() .
Int8Array.prototype.indexOf()
Returns the first(least)index of an element within the array equal to the specified value, or -1 if none is found. See also Array.prototype.indexOf() .
Int8Array.prototype.join()
Joins all elements of an array into a string. See also Array.prototype.join() .
Int8Array.prototype.keys()
Returns a new Array Iterator that contains the keys for each index in the array. See also Array.prototype.keys() .
Int8Array.prototype.lastIndexOf()
Returns the last(greatest)index of an element within the array equal to the specified value, or -1 if none is found. See also Array.prototype.lastIndexOf() .
Int8Array.prototype.map()
返回一个由回调函数的返回值组成的新数组。. See also Array.prototype.map() .
Int8Array.prototype.move() 未实现
Int8Array.prototype.copyWithin() 早期的不标准定义。
Int8Array.prototype.reduce()
从左到右为每个数组元素执行一次回调函数,并把上次回调函数的返回值放在一个暂存器中传给下次回调函数,并返回最后一次回调函数的返回值。参照 Array.prototype.reduce() .
Int8Array.prototype.reduceRight()
从右到左为每个数组元素执行一次回调函数,并把上次回调函数的返回值放在一个暂存器中传给下次回调函数,并返回最后一次回调函数的返回值。参照 Array.prototype.reduceRight() .
Int8Array.prototype.reverse()
颠倒数组中元素的排列顺序,即原先的第一个变为最后一个,原先的最后一个变为第一个。参照 Array.prototype.reverse() .
Int8Array.prototype.set()
Stores multiple values in the typed array, reading input values from a specified array.
Int8Array.prototype.slice()
抽取当前数组中的一段元素组合成一个新数组。参照 Array.prototype.slice() .
Int8Array.prototype.some()
如果数组中至少有一个元素满足测试函数,则返回 true,否则返回 false。参照 Array.prototype.some() .
Int8Array.prototype.sort()
对数组元素进行排序,并返回当前数组.参照 Array.prototype.sort() .
Int8Array.prototype.subarray()
返回一个以给定的初始结束位置裁剪的Int8Array数组.
Int8Array.prototype.values()
返回一个数组迭代器对象,该迭代器会包含所有数组元素的值。.参照 Array.prototype.values() .
Int8Array.prototype.toLocaleString()
返回一个由所有数组元素组合而成的本地化后的字符串. See also Array.prototype.toLocaleString() .
Int8Array.prototype.toString()
返回一个由所有数组元素组合而成的字符串.参照 Array.prototype.toString() .
Int8Array.prototype[@@iterator]()
此方法返回一个带有数组内所有元素的迭代器对象,同Int8Array.prototype.values 。

示例

// 以长度参数构造对象
var int8 = new Int8Array(2);
int8[0] = 42;
console.log(int8[0]); // 42
console.log(int8.length); // 2
console.log(int8.BYTES_PER_ELEMENT); // 1

// 以数组构造对象
var arr = new Int8Array([21,31]);
console.log(arr[1]); // 31

// 从另一数组构造对象
var x = new Int8Array([21, 31]);
var y = new Int8Array(x);
console.log(y[0]); // 21

// 从ArrayBuffer构造对象
var buffer = new ArrayBuffer(8);
var z = new Int8Array(buffer, 1, 4);