freeCodeCamp/curriculum/challenges/chinese-traditional/06-quality-assurance/quality-assurance-and-testing-with-chai/test-if-a-value-is-a-string.md

---
id: 587d824d367417b2b2512c52
title: 測試某個值是否爲字符串
challengeType: 2
forumTopicId: 301599
dashedName: test-if-a-value-is-a-string
---

# --description--

請注意，本項目在[這個 Replit 項目](https://replit.com/github/freeCodeCamp/boilerplate-mochachai)的基礎上進行開發。你也可以從 [GitHub](https://repl.it/github/freeCodeCamp/boilerplate-mochachai) 上克隆。

`isString` 或 `isNotString` 斷言一個值是否爲字符串。

# --instructions--

在 `tests/1_unit-tests.js` 中，`Strings` 套件裏標有 `#13` 的測試下，將每個 `assert` 改成 `assert.isString` 或 `assert.isNotString` 方法，通過測試（結果應該返回 `true`）。 不要修改傳給斷言的參數。

# --hints--

應通過所有測試。

```js
(getUserInput) =>
  $.get(getUserInput('url') + '/_api/get-tests?type=unit&n=12').then(
    (data) => {
      assert.equal(data.state, 'passed');
    },
    (xhr) => {
      throw new Error(xhr.responseText);
    }
  );
```

應該爲第一個斷言選擇正確的方法：`isString` 或 `isNotString`。

```js
(getUserInput) =>
  $.get(getUserInput('url') + '/_api/get-tests?type=unit&n=12').then(
    (data) => {
      assert.equal(
        data.assertions[0].method,
        'isNotString',
        'A float number is not a string'
      );
    },
    (xhr) => {
      throw new Error(xhr.responseText);
    }
  );
```

應該爲第二個斷言選擇正確的方法：`isString` 或 `isNotString`。

```js
(getUserInput) =>
  $.get(getUserInput('url') + '/_api/get-tests?type=unit&n=12').then(
    (data) => {
      assert.equal(
        data.assertions[1].method,
        'isString',
        'environment vars are strings (or undefined)'
      );
    },
    (xhr) => {
      throw new Error(xhr.responseText);
    }
  );
```

應該爲第三個斷言選擇正確的方法：`isString` 或 `isNotString`。

```js
(getUserInput) =>
  $.get(getUserInput('url') + '/_api/get-tests?type=unit&n=12').then(
    (data) => {
      assert.equal(data.assertions[2].method, 'isString', 'A JSON is a string');
    },
    (xhr) => {
      throw new Error(xhr.responseText);
    }
  );
```

# --solutions--

```js
/**
  Backend challenges don't need solutions, 
  because they would need to be tested against a full working project. 
  Please check our contributing guidelines to learn more.
*/
```