顺便说一句，另一种长手方法：
function getCommon(a) {
// default result is copy of first array
var result = a[0].slice();
var mem, arr, found = false;
// For each member of result, see if it's in all other arrays
// Go backwards so can splice missing entries
var i = result.length;
while (i--) {
mem = result[i];
// Check in each array
for (var j=1, jLen=a.length; j<jLen; j++) {
arr = a[j];
found = false;
// For each member of arr and until found
var k = arr.length;
while (k-- && !found) {
// If found in this array, set found to true
if (mem == arr[k]) {
found = true;
}
}
// if word wasn't found in this array, remove it from result and
// start on next member of result, skip remaining arrays.
if (!found) {
result.splice(i,1);
break;
}
}
}
return result;
}
var data = [
['taco', 'fish', 'apple', 'pizza', 'mango', 'pear'],
['apple', 'orange', 'banana', 'pear', 'fish', 'pancake', 'taco', 'pizza'],
['banana', 'pizza', 'fish', 'apple'],
['banana', 'pizza', 'fish', 'apple', 'mango', 'pear']
];
编辑
在 Object.prototype 上基于 thise 查找永远无法枚举的属性的功能：
// Return an array of Object.prototype property names that are not enumerable
// even when added directly to an object.
// Can be helpful with IE as properties like toString are not enumerable even
// when added to an object.
function getNeverEnumerables() {
// List of Object.prototype property names plus a random name for testing
var spNames = 'constructor toString toLocaleString valueOf ' +
'hasOwnProperty isPrototypeOf propertyIsEnumerable foo';
var spObj = {foo:'', 'constructor':'', 'toString':'', 'toLocaleString':'', 'valueOf':'',
'hasOwnProperty':'', 'isPrototypeOf':'', 'propertyIsEnumerable':''};
var re = [];
// BUild list of enumerable names in spObj
for (var p in spObj) {
re.push(p);
}
// Remove enumerable names from spNames and turn into an array
re = new RegExp('(^|\\s)' + re.join('|') + '(\\s|$)','g');
return spNames.replace(re, ' ').replace(/(^\s+)|\s\s+|(\s+$)/g,'').split(' ');
}
document.write(getNeverEnumerables().join('<br>'));