---
id: 56533eb9ac21ba0edf2244e0
title: Replacing If Else Chains with Switch
challengeType: 1
videoUrl: ''
localeTitle: 如果用交换机替换其他链条
---
## Description
如果您有许多选项可供选择，那么switch语句比许多链接的if / else if语句更容易编写。下列： if（val === 1）{
answer =“a”;
} else if（val === 2）{
answer =“b”;
} else {
answer =“c”;
}
可以替换为： switch（val）{
情况1：
answer =“a”;
打破;
案例2：
answer =“b”;
打破;
默认：
answer =“c”;
}
## Instructions
将链接的if / else if语句更改为switch语句。
## Tests
```yml
tests:
- text: 您不应该在编辑器中的任何位置使用任何else语句
testString: assert(!/else/g.test(code));
- text: 您不应在编辑器中的任何位置使用任何if语句
testString: assert(!/if/g.test(code));
- text: 你应该至少有四个break语句
testString: assert(code.match(/break/g).length >= 4);
- text: chainToSwitch("bob")应该是“Marley”
testString: assert(chainToSwitch("bob") === "Marley");
- text: chainToSwitch(42)应该是“答案”
testString: assert(chainToSwitch(42) === "The Answer");
- text: chainToSwitch(1)应该是“没有＃1”
testString: "assert(chainToSwitch(1) === \"There is no #1\");"
- text: chainToSwitch(99)应该是“错过了我这么多！”
testString: assert(chainToSwitch(99) === "Missed me by this much!");
- text: chainToSwitch(7)应该是“Ate Nine”
testString: assert(chainToSwitch(7) === "Ate Nine");
- text: chainToSwitch("John")应为“”（空字符串）
testString: assert(chainToSwitch("John") === "");
- text: chainToSwitch(156)应为“”（空字符串）
testString: assert(chainToSwitch(156) === "");
```
## Challenge Seed
```js
function chainToSwitch(val) {
var answer = "";
// Only change code below this line
if (val === "bob") {
answer = "Marley";
} else if (val === 42) {
answer = "The Answer";
} else if (val === 1) {
answer = "There is no #1";
} else if (val === 99) {
answer = "Missed me by this much!";
} else if (val === 7) {
answer = "Ate Nine";
}
// Only change code above this line
return answer;
}
// Change this value to test
chainToSwitch(7);
```
## Solution
```js
// solution required
```