Question

我有一个包含我所有数据的JSON文件，我想在我的脚本中将其读取到一个数组中。下面你可以看到一个尝试，但似乎“道具”实际上并没有获取数据。因为我是javascript的新手我猜测有一些简单的遗漏，希望有人能告诉我在加载数组时我做错了什么。

如果我在循环内调用alert（记录），它会在每个循环中输出“0”，“1”，“2”递增，如果我尝试提醒（record.Address1）它返回“undefined”，这是怎么回事？工作？

var props = [];
$.getJSON('http://someurl/auction.json', function(json) {
    for (var record in json)
    {
        props.push(
            record.Address1,
            record.City,
            record.State,
            record.Zip,
            record.Bed,
            record.Bath,
            record.Price,
            record.LotSize,
            record.SQFT,
            record.YearBuilt,
            "10%",
            record.latitude,
            record.longitude,
            record.Description  
        );  
    }      
});

以下是JSON文件中的前几个记录

    [
      {
        "TrusteeNumber":"WA-14-611878-TC",
        "Date":"8/8/2014 8:00",
        "Address1":"7616 East Nora Avenue",
        "Address2":"",
        "County":"Spokane",
        "State":"WA",
        "Zip":99212,
        "Description":"Description for 7616 East Nora Avenue, Spokane Valley, Spokane, WA 99212\n\n\n\n\n  \n Important Documents \n\n\nTrustee Sale Terms and Conditions  \n\nSample Trustee Deed Upon Sale  \n\nSample Certificate of Sale/Receipt  \n\nIRS Form 8300",
        "City":"Spokane Valley",
        "AssetType":"Residential",
        "PropertyType":"SFR",
        "Beds":3,
        "Baths":1,
        "YearBuilt":1950,
        "SQFT":"1,160",
        "LotSize":0.25,
        "APN":"45073 0265",
        "EventItemNumber":"E2010-320",
        "PropertyID":1706957,
        "Image":"http://cdn.mlhdocs.com/rcp_files/auctions/E-2010/photos/thumbnails/155290117-1_bigThumb.jpg",
        "latitude":47.672913,
        "longitude":-117.301561
      },
      {
        "TrusteeNumber":"WA-14-611501-TC",
        "Date":"8/8/2014 8:00",
        "Address1":"235 W Columbia Ave",
        "Address2":"",
        "County":"Spokane",
        "State":"WA",
        "Zip":99205,
        "Description":"Description for 235 W Columbia Ave, Spokane, Spokane, WA 99205\n\n\n\n\n  \n Important Documents \n\n\nTrustee Sale Terms and Conditions  \n\nSample Trustee Deed Upon Sale  \n\nSample Certificate of Sale/Receipt  \n\nIRS Form 8300",
        "City":"Spokane",
        "AssetType":"Residential",
        "PropertyType":"SFR",
        "Beds":3,
        "Baths":3,
        "YearBuilt":1947,
        "SQFT":"3,151",
        "LotSize":0.15,
        "APN":"36311 3601",
        "EventItemNumber":"E2010-307",
        "PropertyID":1707641,
        "Image":"http://cdn.mlhdocs.com/rcp_files/auctions/E-2010/photos/thumbnails/208185496-1_bigThumb.jpg",
        "latitude":47.7107249,
        "longitude":-117.415536
      }]

Answer 1

用于迭代json变量的循环在其他编程语言中的行为与foreach不同。相反，它表现得像普通的for循环，它将遍历via index。因此，要使用json集合，您需要修改代码，如下所示：

for (var record in json)
{
    props.push(
        json[record].Address1,
        json[record].City,
        json[record].State,
        ....
    );  
}

或者你也可以在下面尝试，这与其他编程语言中的foreach一样：

$(json).each(function(index, record) {
    props.push(
        record.Address1,
        record.City,
        record.State,
        ....
    );
});

希望这会有所帮助。

Answer 2

使用for (var record in json)，record实际上不是记录，因为它的警报很明显，它所做的是枚举对象中的属性名称，因为json是一个数组记录，该数组的索引如果您想要数组的记录，则必须执行json[record].Address1。

我还建议不要在数组中使用for循环，

for (i = 0; i < json.length; i++)

更清楚地表明你正在循环一个数组

Answer 3

您的for循环未正确使用，在for( var record in json )中，record是索引，在本例中为0, 1。让它工作试试这个：

for (var key in json)
    {
        var record = json[key];
        props.push(
            record.Address1,
            record.City,
            record.State,
            record.Zip,
            record.Bed,
            record.Bath,
            record.Price,
            record.LotSize,
            record.SQFT,
            record.YearBuilt,
            "10%",
            record.latitude,
            record.longitude,
            record.Description  
        );

Answer 4

我已经在代码中的几个不同位置警告了props变量，并注释了它在哪里为null以及它在哪里有内容。我还在我解决问题的那一行添加了评论。基本上调用函数，而props仍然有一个值，并从那里将该数据分配给全局变量。如果没有函数，则无法直接分配给全局。

   <script type="text/javascript">

       var props = [], returnData;
    function initialize() {
$(document).ready(function() {
    $.ajax({
        url: "http://5i2.us/jacksonmashup/allResults.json",
        async: false,
        dataType: 'json',
        success: function (data) {
            returnData = data;
        }
    });

    var len = returnData.length;
    for (var i = 0; i < len; i++){
        var record = returnData[i];
        props.push([
            '<img src="' + record.Type + '"/>',
            record.Address1,
            record.City,
            record.State,
            record.Zip,
            record.Beds,
            record.Baths,
            record.Price,
            record.SQFT,            
            record.LotSize,
            '10%',
            record.latitude,
            record.longitude,
            record.Description,
            record.Image,
            record.Type]
        )               
    };
       });
   }
 </script>

JSON to Array无法正常工作

4 个答案: