json和多维数组

Question

我有一个像这样的多维数组

Array
(
    [1] => Array
        (
            [product_id] => 1
            [product_model] => HFJ5G1.5
            [product_type] => plat
            [product_return] => graviteits

        )

    [2] => Array
        (
            [product_id] => 2
            [product_model] => HHJ5S2.5
            [product_type] => holle plunjer
            [product_return] => veer       

        )
    );  //Only 2 are shown here i have around 110 values

我将此编码为json

json_encode($array);

结果jsonString是这样的

{"1":{"product_id":"1","product_model":"HFJ5G1.5","product_type":"plat","product_return":"graviteits"},"2":{"product_id":"2","product_model":"HHJ5S2.5","product_type":"holle plunjer","product_return":"veer"}}

当我做警报(jsonString.length); 结果是4但我希望结果是凌晨2点我做错了什么.

Answer 1

对象文字没有 .length

您可以使用此方法计算属性:

var count = 0;

for (i in jsonString) {
    if (jsonString.hasOwnProperty(i)) {
        count++;
    }
}

alert(count); //count shall have length for you

要么

由于你的数组没有数字索引(从0开始),它假设你使用了一个关联数组,因此它们转储了一个项目对象而不是一个项目数组.

要将它们转换为数字索引,您所要做的就是在将它们编码为json之前使用array_values:

json_encode(array_values($array));

然后json将是一个数组.. 然后你可以使用长度

由此:

Array(
[1] => Array(
        [product_id] => 1
        [product_model] => HFJ5G1.5
        [product_type] => plat
        [product_return] => graviteits
    )
[2] => Array(
        [product_id] => 2
        [product_model] => HHJ5S2.5
        [product_type] => holle plunjer
        [product_return] => veer       
    )
);

使用array_values()成为这个,记下每个项目的索引:

Array(
[0] => Array(
        [product_id] => 1
        [product_model] => HFJ5G1.5
        [product_type] => plat
        [product_return] => graviteits
    )
[1] => Array(
        [product_id] => 2
        [product_model] => HHJ5S2.5
        [product_type] => holle plunjer
        [product_return] => veer       
    )
);

然后编码为json并存储到jsonString:

jsonString = [
    {
        "product_id": "1",
        "product_model": "HFJ5G1.5",
        "product_type": "plat",
        "product_return": "graviteits"
    },
    {
        "product_id": "2",
        "product_model": "HHJ5S2.5",
        "product_type": "holle plunjer",
        "product_return": "veer"
    }
];

alert(jsonString.length);