---
id: afcc8d540bea9ea2669306b6
title: Repeat a String Repeat a String
isRequired: true
challengeType: 5
videoUrl: ''
localeTitle: 重复一个字符串重复字符串
---
## Description
为num times（第二个参数）重复给定的字符串str （第一个参数）。如果num不是正数，则返回空字符串。如果卡住，请记得使用Read-Search-Ask 。编写自己的代码。
## Instructions
## Tests
```yml
tests:
- text: 'repeatStringNumTimes("*", 3)应该返回"***" 。'
testString: 'assert(repeatStringNumTimes("*", 3) === "***", "repeatStringNumTimes("*", 3) should return "***".");'
- text: 'repeatStringNumTimes("abc", 3)应该返回"abcabcabc" 。'
testString: 'assert(repeatStringNumTimes("abc", 3) === "abcabcabc", "repeatStringNumTimes("abc", 3) should return "abcabcabc".");'
- text: 'repeatStringNumTimes("abc", 4)应返回"abcabcabcabc" 。'
testString: 'assert(repeatStringNumTimes("abc", 4) === "abcabcabcabc", "repeatStringNumTimes("abc", 4) should return "abcabcabcabc".");'
- text: 'repeatStringNumTimes("abc", 1)应该返回"abc" 。'
testString: 'assert(repeatStringNumTimes("abc", 1) === "abc", "repeatStringNumTimes("abc", 1) should return "abc".");'
- text: 'repeatStringNumTimes("*", 8)应该返回"********" 。'
testString: 'assert(repeatStringNumTimes("*", 8) === "********", "repeatStringNumTimes("*", 8) should return "********".");'
- text: 'repeatStringNumTimes("abc", -2)应返回"" 。'
testString: 'assert(repeatStringNumTimes("abc", -2) === "", "repeatStringNumTimes("abc", -2) should return "".");'
- text: 不应使用内置的repeat()方法
testString: 'assert(!/\.repeat/g.test(code), "The built-in repeat()-method should not be used");'
```
## Challenge Seed
```js
function repeatStringNumTimes(str, num) {
// repeat after me
return str;
}
repeatStringNumTimes("abc", 3);
```
## Solution
```js
// solution required
```