slice,splice,split,push,pop,shift,unshift,concat,sort,reverse...

1.arry.slice(start,end)
var a=[1,2,3,4,5,6];
var b=a.slice(0,3); //[1,2,3] The last bit is not taken, the original array a remains unchanged


2.string.slice(start,end)
var a="I am a boy";
var b=a.slice(0,6) //The last digit of "I am a" is not taken, the original array a remains unchanged




3.array.splice(start,deleteCount,item...)
var a=['a','b','c'];
var b=a.splice(1,1,'e','f'); //a=['a','b','f','c'],b=['b'] replace the value of a, which returns the deleted value


4.string.split(separator,limit)
var a="0123456";
var b=a.split("",3)      //b=['0','1','2']


5.arrayObject.push(newelem1,newelem2,....)
var a=[1,2,3,4,5];
va b=a.push(6,7); //a=[1,2,3,4,5,6,7],b=7 The original array is changed, return the changed length


6.arrayObject.pop()
var a=[1,2,3,4,5];
var b=a.pop(); //a=[1,2,3,4],b=5 Change the original array and return the last value that was deleted


7.arrayObject.shift()
var a=[1,2,3,4,5];
var b=a.shift() //a=[2,3,4,5],b=1 Change the original array and return the first value that was deleted


8.arrayObject.unshift()
var a=[1,2,3,4,5];
var b=a.unshift(0) //a=[0,1,2,3,4,5],b=6 Change the original array and return the first value that was deleted


9.arrayObject.concat(array1,array2,...)
var a=[1,2,3,4,5];
var a2=['a','b','c'];
var a3=['d',6];
var b=a.concat(a2,a3) //a,a2,a3 do not change, b=[1, 2, 3, 4, 5, "a", "b", "c", "d", 6] return new array


10.arrayObject.sort(sortby)
var a=[1,2,3,4,5];
a.sort(function(a,b){
return b-a;
}) //a=[5, 4, 3, 2, 1] Sort and reorganize the original array


11.arrayObject.reverse()
var a=[1,2,3,4,5];
a.reverse() //a=[5, 4, 3, 2, 1] reverse continuation


12.object.toSource //!!!!!!!!!!! only supported by Gecko
function employee(name,job,born)
{
this.name=name;
this.job=job;
this.born=born;
}
var bill=new employee("Bill Gates","Engineer",1985);
console.log(bill.toSource())   //({name:"Bill Gates", job:"Engineer", born:1985})


13.booleanObject.toString
var boo = new Boolean(true);
console.log(boo.toString()); //returns the string true
Return Value Returns the string "true" or "false" based on the primitive boolean value or the value of the booleanObject object. If the object on which the method is called is not a Boolean, an exception TypeError is thrown.


14.object.toLocalString
var d = new Date()
document.write(d.toLocaleString()) //The local time converts the Date object to a string and returns the result.


15.booleanObject.valueOf()
var boo = new Boolean(false);
console.log(boo.valueOf()); //return false
The return value is a primitive boolean value of booleanObject. If the object on which the method is called is not a Boolean, an exception TypeError is thrown.