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								title: Replacing If Else Chains with Switch
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											2018-10-04 14:47:55 +01:00
										 
									 
								 
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								## Replacing If Else Chains with Switch
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								<!-- The article goes here, in GitHub-flavored Markdown. Feel free to add YouTube videos, images, and CodePen/JSBin embeds  -->
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								Here’s the setup:
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								```javascript
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								function chainToSwitch(val) {
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								  var answer = "";
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								  // Only change code below this line
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								  switch(val) {
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								    case "bob":
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								        answer = "Marley";
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								        break;
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								    case 42:
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								        answer = "The Answer";
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								        break;
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								    case 1:
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								        answer = "There is no #1";
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								        break;
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								    case 99:
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								        answer = "Missed me by this much!";
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								        break;
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								    case 7:
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								        answer = "Ate Nine";
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								        break;
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								  }
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								  // Only change code above this line
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								  return answer;
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								}
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								// Change this value to test
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								chainToSwitch(7);
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								```
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								We need to change the chained ```if/else if``` statements into a ```switch``` statement.
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								 Here’s a solution:
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								 Now, we need to comment (```//``` - select all lines and ```ctrl+/```) all chained ```if/else if``` statements:
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								 ```javascript
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								 //   if (val === "bob") {
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								//     answer = "Marley";
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								//   } else if (val === 42) {
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								//     answer = "The Answer";
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								//   } else if (val === 1) {
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								//     answer = "There is no #1";
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								//   } else if (val === 99) {
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								//     answer = "Missed me by this much!";
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								//   } else if (val === 7) {
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								//     answer = "Ate Nine";
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								//   }
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								 ```
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								 Next, we need to create simple ```switch``` statement:
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								 ```javascript
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								 switch(val) {
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								 }
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								 ```
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								 and add in this ```switch``` statement ```case``` - for all ```if/else if``` statement (just copy it from our commented code above):
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								  ```javascript
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								  switch(val) {
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								    case "bob":
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								        answer = "Marley";
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								        break;
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								    case 42:
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								        answer = "The Answer";
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								        break;
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								    case 1:
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								        answer = "There is no #1";
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								        break;
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								    case 99:
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								        answer = "Missed me by this much!";
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								        break;
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								    case 7:
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								        answer = "Ate Nine";
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								        break;
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								  }
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								  ```
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								 Dont forget to use ```break``` in each ```case```!
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								 Now, we can delete commented code with ```if/else if``` statement above.
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								 Here’s a full solution:
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								 ```javascript
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								 function chainToSwitch(val) {
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								  var answer = "";
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								  // Only change code below this line
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								  switch(val) {
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								    case "bob":
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								        answer = "Marley";
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								        break;
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								    case 42:
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								        answer = "The Answer";
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								        break;
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								    case 1:
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								        answer = "There is no #1";
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								        break;
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								    case 99:
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								        answer = "Missed me by this much!";
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								        break;
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								    case 7:
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								        answer = "Ate Nine";
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								        break;
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								  }
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								  // Only change code above this line
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								  return answer;
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								}
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								// Change this value to test
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								chainToSwitch(7);
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								 ```
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