jQuery“TypeError：无效的'in'操作数a”
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jQuery "TypeError: invalid 'in' operand a"
提问by Mariano
I have the following json array returning from an ajax call:
我有以下 json 数组从 ajax 调用返回：
{"err":"err_type","fields":["field1","field2"]}
{"err":"err_type","fields":["field1","field2"]}
when tryin to print it out with this function:
当尝试使用此功能打印出来时：
$.each(data.fields, function (i, field) {
console.log(field);
$.each(field, function (j, f) {
$('[name="'+f+'"]').addClass('form_err');
console.log(f);
});
});
i get this:
我明白了：
data1
TypeError: invalid 'in' operand a
...turn function(b){return db(a,b).length>0}}),contains:fb(function(a){return funct...
and so i can't figure out how to use this array! Anyone have any idea?
所以我不知道如何使用这个数组！任何人有任何想法？
回答by Anton
You are iterating a string, you don't need two .each() functions
您正在迭代一个字符串，您不需要两个 .each() 函数
$.each(data.fields, function (i, field) {
$('[name="'+field+'"]').addClass('form_err');
console.log(field);
});
回答by Waweru wa Kamau
Remember to add dataType: 'json';so that it can be looped as an array and not a string.
请记住添加，dataType: 'json';以便它可以作为数组而不是字符串循环。
回答by Jai
You don't need another loopin $.each():
你不需要另一个循环$.each()：
$.each(data.fields, function (i, field) {
console.log(field);
$('[name="'+field+'"]').addClass('form_err');
});
data.fieldsis an array which contains stringsonly, so you don't need to loopin again. You just need to loopin only when if it would be another array object with {key:value}pairs.
data.fields是一个strings只包含的数组，所以你不需要再次循环。只有当它是另一个{key:value}成对的数组对象时，您才需要循环。
回答by Adrien LUCAS
In your main loop, the "field" var is not an array, so you can't use "each" on it.
在您的主循环中，“字段”变量不是数组，因此您不能在其上使用“每个”。
