代码之家 › 专栏 › 技术社区 › Jay Corbett

javascript数组引用

json javascript

Jay Corbett · 技术社区 · 17 年前

如果我有以下信息:

{"hdrs": ["Make","Model","Year"],
 "data" : [ 
   {"Make":"Honda","Model":"Accord","Year":"2008"}
   {"Make":"Toyota","Model":"Corolla","Year":"2008"}
   {"Make":"Honda","Model":"Pilot","Year":"2008"}]
}

我有一个“hdrs”的名字(即“make”),我怎样才能引用 data 数组实例? 好像 data["Make"][0] 应该有效……但无法获得正确的引用

编辑

不好意思含糊不清。我可以循环通过 hdrs 获取每个HDR名称,但我需要使用 HDRS 查找中的所有数据元素 数据 (不确定这是不是更好的解释)。我会把它放在一个变量里 t 因为它是JSON(感谢重新标记),所以我希望能够引用如下内容: t.data[hdrs[i]][j]

9 回复 | 直到 17 年前

Jared xxtesaxx 17 年前

我不得不稍微修改一下你的代码:

var x = {"hdrs": ["Make","Model","Year"],
         "data" : [ 
           {"Make":"Honda","Model":"Accord","Year":"2008"},
           {"Make":"Toyota","Model":"Corolla","Year":"2008"},
           {"Make":"Honda","Model":"Pilot","Year":"2008"}]
        };

        alert( x.data[0].Make );

编辑:响应您的编辑

var x = {"hdrs": ["Make","Model","Year"],
         "data" : [ 
           {"Make":"Honda","Model":"Accord","Year":"2008"},
           {"Make":"Toyota","Model":"Corolla","Year":"2008"},
           {"Make":"Honda","Model":"Pilot","Year":"2008"}]
        };
var Header = 0; // Make
for( var i = 0; i <= x.data.length - 1; i++ )
{
    alert( x.data[i][x.hdrs[Header]] );
}

Domenic 17 年前

那么,像这样?

var theMap = /* the stuff you posted */;
var someHdr = "Make";
var whichIndex = 0;
var correspondingData = theMap["data"][whichIndex][someHdr];

如果我能正确理解你的话,那就行了…

Kent Fredric 17 年前

var x = {"hdrs": ["Make","Model","Year"],
 "data" : [ 
   {"Make":"Honda","Model":"Accord","Year":"2008"}
   {"Make":"Toyota","Model":"Corolla","Year":"2008"}
   {"Make":"Honda","Model":"Pilot","Year":"2008"}]
};

x.data[0].Make == "Honda"
x['data'][0]['Make']  == "Honda"

您的数组/哈希查找向后进行:)

noah 17 年前

我不确定我理解你的问题,但是…

假设上面的json是var obj,您需要:

obj.data[0]["Make"] // == "Honda"

如果您只想引用第一个头引用的字段,它将类似于:

obj.data[0][obj.hdrs[0]] // == "Honda"

just mike 17 年前

首先,您忘记了数据数组项中的尾随逗号。

尝试以下操作:

var obj_hash = {
    "hdrs": ["Make","Model","Year"],
    "data" : [
        {"Make":"Honda","Model":"Accord","Year":"2008"},
        {"Make":"Toyota","Model":"Corolla","Year":"2008"},
        {"Make":"Honda","Model":"Pilot","Year":"2008"},
    ]
};

var ref_data = obj_hash.data;

alert(ref_data[0].Make);

@肯特·弗雷德里克:注意最后一个逗号不是严格需要的,但是允许你更容易地移动周围的行(即,如果你在最后一行之后移动或添加,并且没有逗号,你必须特别记住添加一个。我认为最好总是有尾随逗号。)

Adam Weber 17 年前

可能尝试数据[0].make

Stephen Wrighton 17 年前

关上,你会用

var x = data[0].Make;
var z = data[0].Model;
var y = data[0].Year;

DGM 17 年前

所显示的代码在语法上不正确;它需要一些逗号。我要用这个:

$foo = {"hdrs": ["Make","Model","Year"],
 "data" : [ 
   {"Make":"Honda","Model":"Accord","Year":"2008"},
   {"Make":"Toyota","Model":"Corolla","Year":"2008"},
   {"Make":"Honda","Model":"Pilot","Year":"2008"}]
};

然后我可以访问以下数据:

$foo["data"][0]["make"]

Jay Corbett 17 年前

在答案的帮助下(并且在得到内外循环正确之后),我让这个工作:

var t = eval( "(" + request + ")" ) ;
for (var i = 0; i < t.data.length; i++) {
 myTable +=    "<tr>";
 for (var j = 0; j < t.hdrs.length; j++) {
  myTable += "<td>" ;
   if (t.data[i][t.hdrs[j]] == "") {myTable += "&nbsp;" ; }
    else { myTable += t.data[i][t.hdrs[j]] ; }
  myTable += "</td>";
 }
 myTable +=    "</tr>";
}