Javascript麻瓜：callback 是什麼？ For Javascript Muggle: What is callback Simply put: A callback is a function that is to be executed after another function has finished executing — hence the name ‘call back’. More complexly put: In JavaScript, functions are objects. Because of this, functions can take functions as arguments, and can be returned by other functions. Functions that do this are called higher-order functions . Any function that is passed as an argument is called a callback function . Example 1, function sayHello() { console.log('Hello everyone'); } setTimeout(sayHello(), 3000) function sayHello() is a function and it is passed as an argument of the function setTimeout, i.e. the function setTimeout takes the fucntion sayHello() as its argument. setTimeout is called a higher-order function. sayHello() is called a callback function. The callback function sayHello() is executed after 3000 miliseconds is past. Callbacks ...
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Javascript麻瓜的練習：Parse URL Exercise for Javascript Muggle: Parse URL Create a function called parse_URL to parse the URL: https://example.com:4000/folder/page.html?x=y&a=b#section-2 //please refer the link to complete the exercise: https://developer.mozilla.org/zh-TW/docs/Web/API/URL/URL The function should print the following text to the console: source: https://example.com:4000/folder/page.html?x=y&a=b#section-2 protocol: https host: example.com port: 4000 query:x=y,a=b path: /folder/page.html hash: section-2 segments: [ '', 'folder', 'page.html' ] Sample codes ============================================================================= function parse_URL(myURL) { var a = new URL(myURL); urlObj= { source: myURL, host: a.hostname, ...
食譜 Recipe - Butter Cookies 奶油曲奇 Butter Cookies： 低筋麵粉 cake flour：100g 糖 Sugar：35g 香草精 Vanilla extract ：2/1 茶匙 teaspoon 蛋黃 Yolk: 1 鹽 salt：少許 a bit 鮮奶 milk: 15 ml (加鮮奶，只是要在擠花時好擠一點。加太多的話，烤的時候，餅乾的花紋會不見喔。加太少，擠花會擠到手殘廢。自己得在份量上自行斟酌。） 原味 Original flavor：杏仁粉 Almond powder 40g 抹茶 Matcha flavor：杏仁粉 Almond powder 25g，抹茶粉 Matcha powder 15g 巧克力 chocolate flavor：杏仁粉 Almond powder 25g，可可粉 chocolate poweder 15g (The current article has not been finished. I will update it later on .... 本文尚未完成，更新持續中 ...) 原味曲奇 巧克力曲奇