查询结果如下:(key1和key2可以是任意文本)
id key1 key2 value
1 fred apple 2
2 mary orange 10
3 fred banana 7
4 fred orange 4
5 sarah melon 5
...
我希望将数据存储在一个网格中(可能是一个数组),循环所有记录,如下所示:
apple orange banana melon
fred 2 4 7 -
mary - 10 - -
sarah - - - 5
在PHP中,使用关联数组,这将非常简单:
$result['fred']['apple'] = 2;
但是在JavaScript中,像这样的关联数组是行不通的。在阅读了大量的教程后,我所能得到的只有以下内容:
arr=[];
arr[1]['apple'] = 2;
但是arr['fred']['apple'] = 2;
不能工作。我尝试了对象数组,但对象属性不能是自由文本。我读的教程越多,我就越困惑……
欢迎任何想法:)
发布于 2010-12-02 05:13:29
只需使用常规的JavaScript对象,它将以与关联数组相同的方式“读取”。你也必须记得先初始化它们。
var obj = {};
obj['fred'] = {};
if('fred' in obj ){ } // can check for the presence of 'fred'
if(obj.fred) { } // also checks for presence of 'fred'
if(obj['fred']) { } // also checks for presence of 'fred'
// The following statements would all work
obj['fred']['apples'] = 1;
obj.fred.apples = 1;
obj['fred'].apples = 1;
// or build or initialize the structure outright
var obj = { fred: { apples: 1, oranges: 2 }, alice: { lemons: 1 } };
如果您正在查看值,您可能会得到如下所示的内容:
var people = ['fred', 'alice'];
var fruit = ['apples', 'lemons'];
var grid = {};
for(var i = 0; i < people.length; i++){
var name = people[i];
if(name in grid == false){
grid[name] = {}; // must initialize the sub-object, otherwise will get 'undefined' errors
}
for(var j = 0; j < fruit.length; j++){
var fruitName = fruit[j];
grid[name][fruitName] = 0;
}
}
发布于 2010-12-02 05:08:14
如果它不一定是一个数组,你可以创建一个“多维”JS对象...
<script type="text/javascript">
var myObj = {
fred: { apples: 2, oranges: 4, bananas: 7, melons: 0 },
mary: { apples: 0, oranges: 10, bananas: 0, melons: 0 },
sarah: { apples: 0, oranges: 0, bananas: 0, melons: 5 }
}
document.write(myObj['fred']['apples']);
</script>
发布于 2010-12-02 05:06:57
Javascript很灵活:
var arr = {
"fred": {"apple": 2, "orange": 4},
"mary": {}
//etc, etc
};
alert(arr.fred.orange);
alert(arr["fred"]["orange"]);
for (key in arr.fred)
alert(key + ": " + arr.fred[key]);
https://stackoverflow.com/questions/4329092
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