- isArray方法
检验变量是否包含数组数据
var months = ['January', 'Febraury', 'March', 'April', 'May'];
alert(Array.isArray(months)); //true - forEach方法
var months = ['January', 'Febraury', 'March', 'April', 'May'];
months.forEach(function(value, index, fullArray){
alert(value + ' is month number ' + (index+1) + ' of ' + fullArray.length);
}); //循环遍历数组 第一个参数是数组值，第二个是索引，第三个是当前数组。（下面的参数同样如此） - every和some方法
//every方法遍历数组每一个元素，将每一个元素和一个条件比较，都满足返回true,否则为false.
var months = ['January', 'Febraury', 'March', 'April', 'May'];
var every = months.every(function(value, index, fullArray){
return value.indexOf('r') >= 0;
});
alert(every); //false
//some也是遍历数组，但只要任意一个满足条件就返回true，否则为false
var months = ['January', 'Febraury', 'March', 'April', 'May'];
var some = months.some(function(value, index, fullArray){
return value.indexOf('r') >= 0;
});
alert(some); //true - map方法
//返回一个处理后的数组,原数组保持不变
var months = ['January', 'Febraury', 'March', 'April', 'May'];
months.map(function(value, index, fullArray){
return value + ' is month number ' + (index+1) + ' of ' + fullArray.length;
}); // ["January is month number 1 of 5", "Febraury is month number 2 of 5", "March is month number 3 of 5", "April is month number 4 of 5", "May is month number 5 of 5"] - filter方法
var months = ['January', 'Febraury', 'March', 'April', 'May'];
var filterMonths = months.filter(function(value, index, fullArray){
return value.indexOf('r') >= 0;
});
console.log(filterMonths); // ["January", "Febraury", "March", "April"]
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