javascript

Cross-platform, operated on the client Writing location Event-driven Java Script Common events Demo Java Script events

1. Javascript Syntax: case sensitive, weak type (all types are guided and declared with var) Write it in the tag and cannot be placed in the title var num=10; var str=’123a’; var isRight=true; var ch=’c’; ….. Output alert(num); alert(str); –>When the string is in pure JS code, use double quotes, When strings are mixed in an HTML page, use single quotes to avoid conflict with attribute values’ 1. Javascript events —》onclick mouse click event –>onblur loses focus –>onmouseover mouseover –>Since the types in js are weak types, it is very easy to turn into string concatenation when calculating numbers parseint(string); Convert strings into numbers for calculation 2. Anonymous function (similar to the anonymous method of C#’s delegate) Use a method as a variable var func=function(){var sum=0 ;for(var i=1;i<=100;i++){sum+=i;}return sum;}var num= func();alert(num); 3. Object Objects in js can be regarded as constructors When creating an object, you can create object members directly through the object name and member name. As long as they are assigned once, they can be directly used as objects in the future. Use the properties or methods directly function Person(){ this.name=”Zhang San”;this.age=19 ;this.gender=’Male’; this.sayHello=function() {alert(‘Hello, my name is’+this .name+’, this year’+this.age+’years old ,’+’I am’+this. gender+’Classmates.’);//alert(‘Hello, my name…