Map is not a function 5w次，点赞5次，收藏11次。下面的代码报错TpyeError:data. Apr 4, 2023 · Hence, map is not a function or, sometimes, map is undefined. 检查您引入的库是否支持map函数，如果不支持则需要升级库或使用其他同类库。 总之，TypeError: transpiledependencies. map` returns a new array, which is the result of calling the function passed to it on each element in the array. An answer explains that the list state is updated to a non-array type and how to fix it. map` function is not a function in the traditional sense because it does not have a return value. map is not a function error can be a stumbling block, but now you’re equipped to tackle it head-on. props. wordsData. map is not a function」が発生した場合の原因と解決方法を記述してます。配列以外に「map」を使用した場合に発生します。「chrome」や「firefox」や「safari」の各ブラウザのエラーメッセージの画像もキャプチャしてます。. from(data);map不能遍历HTMLCollection类型的数据，必须先将HTMLCollection转换成array。 Function called on the wrong object. wordsData に setState するように、見直されることをお勧めします。 以上、参考になれば幸いです。 Aug 1, 2021 · パターン1：オブジェクトに対してmapを使用 const obj = { a: 1, b: 2 }; obj. prototype. In this example, Array. Aug 11, 2019 · A user asks why they get this error when using . map(item => item. Sep 11, 2023 · Learn why the map() function only works on arrays and how to convert other data types into arrays before using the function. let nameList = data. keys(), Object. To solve the error, console. get is not a function。我们将探讨这个问题发生的原因，并提供解决方法和示例代码。 Apr 17, 2022 · 解決したいことJavascriptでmapを使ってみたところ、関数名 is not a functionと怒られてしまいました。アロー関数の書き方が悪いでしょうか？ご教示ください。発生してい… Jul 22, 2024 · その際に、object. map is in the CollapsibleRecipe component: Aug 3, 2022 · 下面就让小编来带大家学习“React报错map() is not a function的原因是什么”吧! 总览. For certain methods, you have to provide a (callback) function and it will work on specific objects only. 解决办法：经过在控制台打印出需要遍历的数组，发现报错的导出的数组其内部还包裹了一层，则重新定义需要map的数组. map() is not a funcitonというエラーに悩まされたが解決したので方法をメモしておく。 mapはarray(配列)でなければ操作をできないが、jsonのデータはobjectらしい。 その違いは、{}で囲まれているか、[]で囲まれているかである。 Jul 5, 2017 · But when you click the “+” button and add a new recipe, you get the following error: Uncaught TypeError: this. log上，并确保只对有效的数组调用map。 Feb 1, 2020 · Inspect what the data is – log it or put a breakpoint in. log(currentState); For what you are trying to accomplish, you want your state to be the result of the map function (since that returns an array of your results from the map). What we need is a for React to check for data before trying Nov 9, 2022 · javascriptで、エラー「Uncaught TypeError: xxx. log the value you're calling the map() method on and make sure to only call the map() method on valid arrays. keys()方法获取对象的键组成的数组，在该数组上可以调用map()方法。 The `react. map(item => console. get 不是一个函数的解决方法 在本文中，我们将介绍使用 TypeScript 时，从 Map 中检索值时遇到的常见问题：TypeError: map. You are trying to call map on something that isn’t an array and doesn’t have a map method. map is not a function错误通常是因为JavaScript版本兼容性问题、错误的变量类型、引入错误的库等 Jun 15, 2017 · const testArray = [1,2,3,4]; let currentState; //Notice we are using the return value of the map function itself. Jun 12, 2015 · This is a nonsensical solution, and objectively incorrect in the context of the question. entries() methods. values(), and Object. To fix this error, you need to make sure that the value you are passing to `map()` is a function. map((supplier)=>supplier) to (suppliers || []). Your answer causes the entire data object to be passed into getData, which clearly expects one of the elements from data. Also as mentioned above the usage of setstate is not recommended. Let’s see with help of simple example: The “. data or suppliers get changed to null\undefined your app will not crash. isArray(), Object. Apr 18, 2024 · We can use MAP function only on Arrays (particularly array prototypes) not on Objects. 概要javascriptでmapメソッドを使いたかったが以下のエラーが出てきたのでメモ。配列っぽいデータを加工したい場合はmapメソッドを使っとけばいい、と思っていたが、それは曖昧な理解ですべて… Mar 7, 2023 · 下面的代码报错TpyeError:data. map is not a function The call to this. map is not a function” error occurs when you try to use the `map()` method on a value that is not a function. products as its input, not the entire data object. map is not a function error, first figure out the shape of the data you are working with and then create an array from that data depending on what the data is. In ReactJS, the `. And also the Profile data which you are actually searching is inside the "data" key of the data "constant". See examples of using Array. 文章浏览阅读3. products. Jun 16, 2021 · 问题： 在js中使用map的时候，出现了异常：Uncaught TypeError: map. keys. map, not to wrap data in an array. 将 Mar 10, 2021 · You can also change the following line suppliers. map() is used, which will work with Array objects only. com Feb 3, 2024 · The . The process can be printed to the console with a little conditional logic. name); 原因1:data不是数组； 解决方法:将data转换成数组 let data = Array. May 20, 2022 · TypeError: . Apr 13, 2024 · 3. Object. data);. get is not a function，突然感觉后背发凉！ 解决： 经过一番查找，原来是声明map方式的原因，在js中有两种创建map的方式。 Aug 10, 2024 · 问题：将同一个函数解构出来的数组分别导入两个文件并使用，发现其中一个文件导入解构出来的数组用map遍历后出现. map is not a function occurs when we call map() function on object which is not an array. Jun 14, 2020 · で、this. Instead, `react. name);原因1:data不是数组；解决方法:将data转换成数组let data = Array. 一番最初のサンプルコードで書いた例ですね！ objがオブジェクトなのでmapを受け入れてくれません。 Nov 22, 2021 · ・取得したAPIが配列ではないためmapを使用できないと考えました。そこでeachに変えてみましたがエラーは治りませんでした。 そこでeachに変えてみましたがエラーは治りませんでした。 Sep 23, 2024 · For certain methods, you have to provide a (callback) function and it will work on specific objects only. 当我们对一个不是数组的值调用map()方法时，就会产生"TypeError: map is not a function"错误。为了解决该错误，请将你调用map()方法的值记录在console. For example, maybe your data is a simple object but the array you were looking for is actually inside that object. currentState = testArray. map is not a function というエラーになります。 修正方法としては、GETで返されたレスポンスから得られた配列を this. ingredients. map((value) => value) console. It indents the json Aug 19, 2022 · 在调用map方法之前，我们将值转换为数组。这也适用于类数组的对象，比如调用getElementsByClassName方法返回的NodeList。. map() function can be only called on array. map((supplier)=>supplier) this way in case x. The "TypeError: map is not a function" occurs when we call the map() method on a value that is not an array. TypeScript 中的 map. A suggestions: Use this Chrome Extension for viewing the API data. let nameList = data. state. So while setting profile data, just use setProfile(data. log(item)); // Uncaught TypeError: obj. By understanding the root cause and applying the best practices we’ve discussed, you’ll be able to prevent this error from cropping up in your JavaScript journey. Apr 8, 2022 · To solve the object. See full list on bobbyhadz. map is not a function. The answer is to use data. map()` method is used to iterate over an array and return a new array with the results of applying a function to each element of the original array. from(data); map不能遍历HTMLCollection类型的数据，必须先将HTMLCollection转换成array。 Nov 18, 2021 · { // `data` is the response that was provided by the server data: {}, // `status` is the HTTP status code from the server response status: 200, // `statusText` is the HTTP status message from the server response statusText: 'OK', // `headers` the HTTP headers that the server responded with // All header names are lower cased and can be accessed using the bracket notation. 如果你尝试迭代遍历对象，使用Object. map() on a list state in ReactJS. gijjlyoqupczbhyjlgmaasoejvphxqvndkwldgmvewcevlqvdudnfzjjyuyssyus