jQuery data.map 不是函数
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data.map is not a function
提问by mrcat
I'm bashing my head against an error I can't work out how to fix. I have the following;
我正在为一个我无法解决的错误而烦恼。我有以下内容；
JSON
JSON
{"products":
[
{
"product_id" : "123",
"product_data" : {
"image_id" : "1234",
"text" : "foo",
"link" : "bar",
"image_url" : "baz"
}
},{
"product_id" : "456",
"product_data" : {
"image_id" : "1234",
"text" : "foo",
"link" : "bar",
"image_url" : "baz"
}
}
]}
and the following jQuery
和以下 jQuery
function getData(data) {
this.productID = data.product_id;
this.productData = data.product_data;
this.imageID = data.product_data.image_id;
this.text = data.product_data.text;
this.link = data.product_data.link;
this.imageUrl = data.product_data.image_url;
}
$.getJSON("json/products.json").done(function (data) {
var allProducts = data.map(function (item) {
return new getData(item);
});
});
yet I'm getting an error that map.data is undefined as a function? Looking at it I don't know what's not working as I've copied this to a new project from previously used code. The only thing different is the JSON source. The previous one didn't have the {"products":part before the [] brackets. Is this what's throwing me off?
但我收到一个错误，map.data 未定义为函数？看着它，我不知道什么不起作用，因为我已将其从以前使用的代码复制到新项目中。唯一不同的是 JSON 源。前一个没有{"products":[] 括号之前的部分。这是让我失望的原因吗？
回答by Henrik Andersson
Objects, {}, in JavaScript does not have the method .map(), it's only for Arrays, [].
Objects, {}, 在 JavaScript 中没有这个方法.map()，它只用于数组，[]。
So in order for your code to work change data.map()to data.products.map()since productsis an array which you can iterate upon.
因此，为了让您的代码工作，更改data.map()为data.products.map()因为products是一个您可以迭代的数组。
回答by user3930374
The right way to iterate over objects is
迭代对象的正确方法是
Object.keys(someObject).map(function(item)...
Object.keys(someObject).forEach(function(item)...;
// ES way
Object.keys(data).map(item => {...});
Object.keys(data).forEach(item => {...});
回答by Arun P Johny
datais not an array, it is an object with an array of products so iterate over data.products
data不是一个数组，它是一个包含一系列产品的对象，所以迭代 data.products
var allProducts = data.products.map(function (item) {
return new getData(item);
});
回答by William Hou
The SIMPLESTanswer is to put "data"into a pair of square brackets (i.e. [data]):
最简单的答案是将“数据”放入一对方括号中（即[data]）：
$.getJSON("json/products.json").done(function (data) {
var allProducts = [data].map(function (item) {
return new getData(item);
});
});
Here, [data]is an array, and the ".map"method can be used on it. It works for me!
这里，[data]是一个数组，可以对它使用“.map”方法。这个对我有用！
回答by Bill King
If you want to map an object you can use Lodash. Just make sure it's installed via NPM or Yarn and import it.
如果你想映射一个对象，你可以使用 Lodash。只需确保它是通过 NPM 或 Yarn 安装并导入的。
With Lodash:
使用洛达什：
Lodash provides a function _.mapValuesto map the values and preserve the keys.
Lodash 提供了一个函数_.mapValues来映射值并保留键。
_.mapValues({ one: 1, two: 2, three: 3 }, function (v) { return v * 3; });
// => { one: 3, two: 6, three: 9 }
回答by Kenlly Acosta
dataneeds to be Json object, to do so please make sure the follow:
数据需要是 Json 对象，为此请确保以下内容：
data = $.parseJSON(data);
Now you can do something like:
现在您可以执行以下操作：
data.map(function (...) {
...
});
I hope this help some one
我希望这对某人有所帮助
回答by Fernando Betancourt
this.$http.get('https://pokeapi.co/api/v2/pokemon')
.then(response => {
if(response.status === 200)
{
this.usuarios = response.data.results.map(usuario => {
return { name: usuario.name, url: usuario.url, captched: false } })
}
})
.catch( error => { console.log("Error al Cargar los Datos: " + error ) } )
回答by Daniel Ryan Snell
You can always do the following:
您始终可以执行以下操作：
const SomeCall = request.get(res => {
const Store = [];
Store.push(res.data);
Store.forEach(item => { DoSomethingNeat
});
});
回答by Giacomo Paita
There is an error on $.map()invocation, try this:
$.map()调用时出错，试试这个：
function getData(data) {
this.productID = data.product_id;
this.productData = data.product_data;
this.imageID = data.product_data.image_id;
this.text = data.product_data.text;
this.link = data.product_data.link;
this.imageUrl = data.product_data.image_url;
}
$.getJSON("json.json?sdfsdfg").done(function (data) {
var allPosts = $.map(data,function (item) {
for (var i = 0; i < item.length; i++) {
new getData(item[i]);
};
});
});
The error in your code was that you made returnin your AJAX call, so it executed only one time.
您的代码中的错误是您return在 AJAX 调用中产生的，因此它只执行了一次。
