Question

我有一个Json对象数组

   posturlContent = [
        { "Title": "Bbc news live", "Content": "<div>this is a test BBC </div>", "Uri": "http://bbc.co.uk" },
        { "Title": "CNN news live", "Content": "<div>this is a test CNN</div>", "Uri": "http://cnn.com" },
        { "Title": "Youtube news live", "Content": "<div>this is a test Youtube </div>", "Uri": "http://youtube.com" },
    ];

我有一个JS数组

uris =["http://cnn.com", "http://abcnews.com",...]

我需要检查posturlContent Json obejct中是否存在任何uris数组元素，还要查找不存在的那些元素。我知道要做的唯一方法是做嵌套循环。

是否更容易.inArray或包含我可以使用的功能？

Answer 1

您可以使用$.grep：

$.grep(posturlContent, function(item){return item.Uri == siteUrl}).length > 0

如果确实如此，则该项目位于数组内。

然后将其包装在$.each：

中

$.each(uris, function(){
    var siteUrl = this.valueOf();
    // Grep and do whatever you need to do.
})

你可以删除这样的项目：

$.each(uris, function(){
    var siteUrl = this.valueOf();
    posturlContent = $.grep(posturlContent, function(item){
        return item.Uri.toLowerCase() != siteUrl.toLowerCase();
    });
})

请注意，我们现在正在过滤与siteUrl不匹配的项目。

Answer 2

如果创建url缓存对象怎么办？这是一个小提琴http://jsfiddle.net/U94xT/1/

var posturlContent = [
    { "Title": "Bbc news live", "Content": "<div>this is a test BBC </div>", "Uri": "http://bbc.co.uk" },
    { "Title": "CNN news live", "Content": "<div>this is a test CNN</div>", "Uri": "http://cnn.com" },
    { "Title": "Youtube news live", "Content": "<div>this is a test Youtube </div>", "Uri": "http://youtube.com" },
];
var uris =["http://cnn.com", "http://abcnews.com"];

var urisCache = {}; // using object to avoid urls duplicates, that could occur using an array
for (var i = 0; i < posturlContent.length; i++) {
    var key = posturlContent[i]["Uri"];
    urisCache[key] = true; // or urisCache[key] = posturlContent[i]; if you need to access the corresponding entry from posturlContent
}

//now check if the uris array element exist in posturlContent
for (var i = 0; i < uris.length; i++) {
     alert(uris[i] in urisCache);
}

Answer 3

你可以通过使用JQuery grep找到exists，并通过改变来找到nonExists;

Array.prototype.diff = function(a) {
  return this.filter(function(i) {return !(a.indexOf(i) > -1);});
};

var exists = [];
jQuery.grep(posturlContent, function(n, i){
  var index = uris.indexOf(n.Uri);
  if(index >=0){
       exists.push(uris[index])
  }
});

var nonExists = uris.diff(exists)

Answer 4

您可以使用grep()查找已存在且不存在的uri。我不确定与编写自己的循环相比有多快，但它肯定更直接

var posturlContent = [
        { "Title": "Bbc news live", "Content": "<div>this is a test BBC </div>", "Uri": "http://bbc.co.uk" },
        { "Title": "CNN news live", "Content": "<div>this is a test CNN</div>", "Uri": "http://cnn.com" },
        { "Title": "Youtube news live", "Content": "<div>this is a test Youtube </div>", "Uri": "http://youtube.com" },
    ];

var uris =["http://cnn.com", "http://abcnews.com"];

//keep track of URI's that exist and that are missing
var found = [];
var missing = [];

//for is faster than each()
for(var i=0; i<uris.length; i++) {
    found.concat($.grep(posturlContent, function(item){return item.Uri === uris[i]}, false));
    missing.concat($.grep(posturlContent, function(item){return item.Uri === uris[i]}, true));
}

//do something with found and missing urls

Answer 5

这是一个没有jQuery的答案，如果没有forEach，你需要旧的浏览器支持......

for(var i =0; i<posturlContent.length; i++) {
  var detail = posturlContent[i];
  for(var j =0; j<uris.length; j++) {
    var uri = uris[j];
    if (detail.Uri === uri) {
      console.log('matched ' + detail.Uri);
    } else {
      console.log('didnt match ' + detail.Uri);
    }
  }
}

如果你想忽略大小而不是===你可以使用： -

if (new RegExp(uri, "i").test(details.Uri))

包含检查JSon对象

5 个答案: