在json中搜索特定的键并查找上一个和下一个相似的键。

Question

与brnwdrng的问题类似，我正在寻找一种方法来搜索类似JSON的对象，并找到上一个类似键和下一个类似键。假设我的对象的结构如下：

TestObj = {
"Categories": [{
    "Products": [{
        "id": "a01",
        "name": "Pine",
        "description": "Short description of pine."
    },
    {
        "id": "a02",
        "name": "Birch",
        "description": "Short description of birch."
    },
    {
        "id": "a03",
        "name": "Poplar",
        "description": "Short description of poplar."
    }],
    "id": "A",
    "title": "Cheap",
    "description": "Short description of category A."
},
{
    "Product": [{
        "id": "b01",
        "name": "Maple",
        "description": "Short description of maple."
    },
    {
        "id": "b02",
        "name": "Oak",
        "description": "Short description of oak."
    },
    {
        "id": "b03",
        "name": "Bamboo",
        "description": "Short description of bamboo."
    }],
    "id": "B",
    "title": "Moderate",
    "description": "Short description of category B."
}]

}；

现在我想找到一个名称为"oak“的标题，在我发现我还想找到"oak”之前的最后一个标题，在本例中是"maple“，下一个标题是”竹子“。

如果有人能为我指出正确的方向，或者给我一个伪代码，我将不胜感激。

谢谢

Answer 1

做一些这样的事情

i = 0;
foreach obj in TestObj
   if obj.title = Oak,
      last_title = TestObj[i].title;
      next_title = TestObj[i+2].title;
      i++;
endfor

Answer 2

好的，这是一个快速的代码。

TestObj = {
"Categories": [{
    "Products": [{
        "id": "a01",
        "name": "Pine",
        "description": "Short description of pine."
    },
    {
        "id": "a02",
        "name": "Birch",
        "description": "Short description of birch."
    },
    {
        "id": "a03",
        "name": "Poplar",
        "description": "Short description of poplar."
    }],
    "id": "A",
    "title": "Cheap",
    "description": "Short description of category A."
},
{
    "Products": [{
        "id": "b01",
        "name": "Maple",
        "description": "Short description of maple."
    },
    {
        "id": "b02",
        "name": "Oak",
        "description": "Short description of oak."
    },
    {
        "id": "b03",
        "name": "Bamboo",
        "description": "Short description of bamboo."
    }],
    "id": "B",
    "title": "Moderate",
    "description": "Short description of category B."
}]
};

var oak, beforeOak, afterOak;

for(var i=0;i<TestObj.Categories.length;i++){
    var products = TestObj.Categories[i].Products;
       for(var j=0; j< products.length;j++){
        var product = products[j];

        if(product.name === 'Oak'){
            oak = product;
            beforeOak = products[j-1];
            afterOak = products[j+1];
            break;

        }
    }
    if(oak) break;
}

alert("Oak : "+JSON.stringify(oak));
alert("Before Oak : "+JSON.stringify(beforeOak));
alert("After Oak :" + JSON.stringify(afterOak));

在这里查看它的实际效果：http://jsfiddle.net/ejDk8/4/

这很容易理解。如果您还不了解JSON，那么JSON是JavaScript的本机对象结构。因此，您可以使用dot表示法访问它。

Starter on JSON in JavaScript

顺便说一下，，你的json有点不一致。第二个类别中数组"Products“的关键字是"Product”，而不是"Products“。所以我擅自改正了它。