27 lines
626 B
Markdown
27 lines
626 B
Markdown
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---
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title: Restrict Possible Usernames
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---
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## Restrict Possible Usernames
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## Solution:
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```javascript
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let username = "JackOfAllTrades";
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let userCheck = /^[a-z]{2,}\d*$/i;
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let result = userCheck.test(username);
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```
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## Explain:
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1. The only numbers in the username have to be at the end. `\d$`
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There can be zero or more of them at the end. `*`
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```javascript
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/\d*$/;
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```
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2. Username letters can be lowercase and uppercase. `i`
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```javascript
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/\d*$/i;
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```
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3. Usernames have to be at least two characters long. `{2,}`
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A two-letter username can only use alphabet letter characters. `^[a-z]`
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```javascript
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/^[a-z]{2,}\d*$/i;
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```
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