JavaScript Learning Basics

ECMAScript: Translation, core, interpreter;

Dom:document object model Operation Html.document;

typeof A;

Nan and Nan are unequal; isNaN is used to detect;

= = Convert the type first, then the comparison, that is, the implicit type conversion, minus is also;

= = = does not convert type, direct comparison;

Closures: Child functions can use local variables of the parent function;

Hungarian nomenclature: Type prefixes (variable), capitalized (function);

% modulo: seeking remainder;

Trinocular operator?: Condition? Statement 1: Statement 2;

Break: Interrupts the whole;

Continue: Interrupt this time, skip this time;

JSON: Var json with curly braces = {a:12,b:5,c: ' abc '};alert (JSON.A);

When looping, arrays can use either for (Var i=0;i<arr.length;i++) or for (Var i in arr), JSON can only use for (Var i in JSON);

Arguments: variable parameter, indefinite parameter;

var a = new Array (All-in-all) and var a = [All-in-all], recommended to use the right;

var a = [1,2,3];a.push (4); Alert (a)//add;

var a = [1,2,3];a.pop (); Alert (a)//delete the last one;

var a = [1,2,3];a.shift (); Alert (a)//delete the first one;

var a = [1,2,3];a.unshift (2); Alert (a)//added to the head;

var a = [1,2,3];a.splice (, ' a '); Alert (a)//delete the 1th start, the length 2 part, and insert A;

var a = [1,2,3];var B = [4,5,6]; Alert (A.concat (b)); Connection

var a = [1,2,3];a.join ('-'); alert (a);//Add a connector;

var a = [A,z,d,y,d,s,j];a.sort (); alert (a);//Sort, only recognize the string, the number will be invalid;

Str.charat (): Fully compatible take a string one;

The month of JS starts from 0 to 11, week: Sunday is 0, and week 6 is 6;

Offsetleft: Consider location information, such as left, such as margin;

position:relative relative positioning;

Overflow:hidden hidden overflow;

List-style:none list character disappears;

JavaScript Learning Basics