33 lines
877 B
Markdown
33 lines
877 B
Markdown
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The notes are below the code:
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```js run
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async function loadJson(url) { // (1)
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let response = await fetch(url); // (2)
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if (response.status == 200) {
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let json = await response.json(); // (3)
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return json;
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}
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throw new Error(response.status);
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}
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loadJson('https://javascript.info/no-such-user.json')
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.catch(alert); // Error: 404 (4)
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```
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Notes:
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1. The function `loadJson` becomes `async`.
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2. All `.then` inside are replaced with `await`.
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3. We can `return response.json()` instead of awaiting for it, like this:
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```js
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if (response.status == 200) {
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return response.json(); // (3)
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}
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```
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Then the outer code would have to `await` for that promise to resolve. In our case it doesn't matter.
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4. The error thrown from `loadJson` is handled by `.catch`. We can't use `await loadJson(…)` there, because we're not in an `async` function.
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