JavaScript Basics 2

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True: true, not 0 digits, non-empty string, non-empty object

False: False, numeric zero, empty string, empty object, undefined

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Json

Cycle:

1. Array for 0--length

2.json for in

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CSS functions

Arguments---indefinite parameter

function sum () {

var result = 0;

for (var i in arguments) {

Result + = Arguments[i];

}

return result;

}

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Take non-inline styles

Cannot take compound style----background,border

OBJ.CURRENTSTYLE[ATTR]//ie

getComputedStyle (Obj,false) [attr]//chrome FF

function GetStyle (obj,attr) {

if (Obj.currentstyle) {

return obj.currentstyle[attr];

}else{

Return getComputedStyle (Obj,false) [attr];

}

}

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Use of arrays

One, add, delete

1. Adding headers

Arr.unshift ();

Trailing add

Arr.push ();

2. Head deletion

Arr.shift ();

Trailing Delete

Arr.pop ();

3. Middle Add, delete

Delete: Splice (beginning, length);

Added: Splice (starting point, 0, Element);

Replace: Splice (starting point, number of elements, element);//delete first, add after

Second, sort, convert

1. Connect

A.concat (b);

A.join ('-');//The elements inside the array are connected with '-'

2. Sorting

    sort ();

        var arr = [123,354,57567,798,90,8,7];         arr.sort (function (i,j) {             /*if (I<J) {                 return -1;             }else if (I>J) {                 return 1;             }else{                return  0;            }*/             return i-j;         });     &nbSp;   window.onload = function () {             alert (arr);        };

JavaScript Basics 2