Question

我正在尝试过滤大型json数据集，我想知道如何垂直选择json对象。

Lat's采取这个小例子，我想选择所有书籍作者名称包含'Evelyn'

data= [ 
      { "category": "reference",
        "author": "Nigel Rees",
        "title": "Sayings of the Century",
        "price":8
      },
      { "category": "fiction",
        "author": "Evelyn Waugh",
        "title": "Sword of Honour",
        "price": 8
      },
      { "category": "fiction",
        "author": "Evelyn Melville",
        "title": "Moby Dick",
        "isbn": "0-553-21311-3",
        "price": 8.99
      },
      { "category": "fiction",
        "author": "J. R. R. Tolkien",
        "title": "The Lord of the Rings",
        "isbn": "0-395-19395-8",
        "price": 22.99
      }

因此我应该得到：

  { "category": "fiction",
            "author": "Evelyn Waugh",
            "title": "Sword of Honour",
            "price": 8
          },
          { "category": "fiction",
            "author": "Evelyn Melville",
            "title": "Moby Dick",
            "isbn": "0-553-21311-3",
            "price": 8.99
          },

我可以这样做：

$.each(data,function(i,el)
{
    var newdata;
     if (data.author.contains('Evelyn')) newdata.push()
});

另一种方式：

 data.where( "( n, i ) => n.author.contains('Evelyn') " ) ;

你有两个方面的问题，解决这个问题的最快方法是什么，因为我拥有庞大的数据集？

Answer 1

您可以使用Array.filter：

var filtered = data.filter(function(a){return +(a.price) >= 8;}

或过滤author字段：

var filtered = data.filter(function(a){return /evelyn/i.test(a.author);});
// now [filtered] contains the objects from [data] 
// where 'author' contains 'Evelyn'
// filtered.length => 2
// filtered[0].category => 'fiction'

MDN filter documentation（包括旧版浏览器的垫片）

Answer 2

你试过这个吗？我在我的一些项目中使用它并且真的可以推荐它。 http://www.hugoware.net/projects/jlinq

Answer 3

您可以使用filter：

data.filter(function(book) {
  return /Evelyn/.test(book.author);
});

Answer 4

contains运算符在这里不起作用，你必须在这里使用indexOf函数。以下代码应该可以正常工作

data= [ 
      { "category": "reference",
        "author": "Nigel Rees",
        "title": "Sayings of the Century",
        "price":8
      },
      { "category": "fiction",
        "author": "Evelyn Waugh",
        "title": "Sword of Honour",
        "price": 8
      },
      { "category": "fiction",
        "author": "Evelyn Melville",
        "title": "Moby Dick",
        "isbn": "0-553-21311-3",
        "price": 8.99
      },
      { "category": "fiction",
        "author": "J. R. R. Tolkien",
        "title": "The Lord of the Rings",
        "isbn": "0-395-19395-8",
        "price": 22.99
      }];

data.forEach(function(args){
    if(args.author.indexOf('Evelyn') >= 0){
        console.log(args);
    }

});

根据条件选择JSon对象

4 个答案: