javascript foreach loop

ExtJS learning ----------- Ext. Array, ExtJS extension to the Array in javascript (example), ext. array. foreach (1) clean Var arr = [1, 2, null, 3, '']; alert (Ext. array. clean (arr); // clean object :( value = null) | (value = undefined) | (! AllowEmptyString? Value = '': false) | (Ext. isArray (value) value. length = 0) // The result is 1, 2, 3.(2) difference // Differencevar arr1 = [, 3]; var arr2

this series as effective JavaScript 's reading notes. Can you see what the last average is for this code?var = [98, scores, Max, Max, 89];var, max = 0;for (var score in scores) {total + = score;} var mean = Total/scores.length;mean; // ?by calculation, the final result should be the . but don't forget toFor : InchLoop, is traversed forever isKey, but notvalue, the same is true for arrays. Therefore the aboveFor : Inchin the Loopscorenot expected.98,

The variables defined in the For loop are also valid outside the For loop body Results:Carl Is:111"Javascript": variables defined in the For loop are also valid outside the For loop body

High-performance JavaScript loop statements and conditional statements, and high-performance javascript I. Cyclic statementsAs we all know, common loop statements include for, while, do-while, for-in, and forEach. In addition to the for-in and

in a stackoverflow Q A,... The difference between in and for (;) is that the former represents the attributes of enumeration objects, and there are two problems: The order of enumeration cannot be guaranteed; The inherited attributes are also enumerated; InArray. prototype. forEachIn this table, we can also clearly see that IE8 and earlier versions cannot be accurately supported: The compatibility of the forEach method is described in detail here.

JavaScript array and loop explanation, and javascript Array explanation An array is an ordered combination of elements. In JavaScript, Arrays can be created using formal Object Notation or initialized using direct quantitative notation. Copy codeThe Code is as follows:Var arrObject = new Array ("val1", "val2"); // acts

the subsequent code will continue to execute.1 function res () {2 var demoarr = [' Javascript ', ' Gulp ', ' CSS3 ', ' Grunt ', ' jQuery ', ' angular '];3 4 For (var item in Demoarr) {5 if (item = = 2) {6 return;7 };8 Console.log (item, Demoarr[item]);9 }Ten console.log (' desc ', ' function res ');//will not be executed One} 3. ForEachDemoarr.foreach (function (ARG) {})The parameter arg represents the element for each item in the array,

This article mainly introduces high-performance JavaScript loop statements and conditional statements. For more information, see I. Cyclic statementsAs we all know, common loop statements include for, while, do-while, for-in, and forEach. In addition to the for-in and forEach