64 lines
1.6 KiB
Markdown
64 lines
1.6 KiB
Markdown
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---
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title: Change Styles Based on Data
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---
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## Change Styles Based on Data
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Remind yourself once again what is the callback function with [this](https://codeburst.io/javascript-what-the-heck-is-a-callback-aba4da2deced)
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There is two ways you can complete this part, either with if-else logic or ternary operator.
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**if-else logic**
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An example from [w3school](https://www.w3schools.com/js/js_if_else.asp)
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```javascript
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const money = 50;
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if (money < 50) {
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return "I\'m rich";
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}
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else {
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return "I`'m poor";
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}
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```
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What you need to remember is the bracket that the if-else logic associate with, (argument) and {statement}
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**Try Yourself Now** 👩💻👨💻
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**Ternary operator**
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A more detailed explanation [here](https://codeburst.io/javascript-the-conditional-ternary-operator-explained-cac7218beeff). Ternary operator is a lot more concise and quicker to remember for a simple true or false statement. Read [this](https://www.thoughtco.com/javascript-by-example-use-of-the-ternary-operator-2037394)
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```javascript
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condition ? value if true : value if false
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```
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For someone who still not sure here is a solution by using If-else statement
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```javascript
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.style("color", (d) => {
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if (d < 20){
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return 'red'
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}
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else {
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return 'green'
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}
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})
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```
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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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