Master js functions
This article mainly shares with you the detailed explanation of js functions. It mainly shares with you three methods of function definition and function calling methods. I hope it can help you.
Definition of js function:
Function keyword: function;
Function definition is composed of, keyword, function name plus a set of parameters, and placed in curly brackets Defined by a piece of code that needs to be executed.
Function name: required. Function names must be unique within the same page and are case-sensitive.
Parameters: optional. Used to specify a parameter list.
Function statement body: required. Statements that implement function functions.
Expression: Optional, used to return function expression.
function 函数名([参数1,参数2,]){ 函数语句体; [ return 表达式;] }
Function definition method;
方法一 var fun1=new Function('{alert("html")}');
方法二 var fun2=function(){ alert("css"); }
方法三 function fun3(){ alert("javascript"); }
Function call:
函数调用; 需要先定义再调用; <script type="text/javascript"> function test(str1,str,){ alert(str1+str2); } test();
Related recommendations:
JS function and variable promotion and closure explanation
Knowledge you need to master about js functions
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