JavaScript函数定义与调用实例解析

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  <script>
    //js函数的书写
    function myFunction() {
      console.log("你好");
    }
//左边是funcion关键字 后面是函数名，里面写表达式
//带参数的两种写法 
//1.在函数里面写实参
    function myFunction(num,time,action) {
      var num=7,time="点",action="起床";
      console.log(num + time + action);
    }
//2.在调用函数的时候写实参
    function myFunction(num,time,action) {
      console.log(num + time + action);
    }
    myFunction("7", "点","起床");
//带返回值写法 
   function myFunction(a,b){
    var a=5,b=6;
    return a+b;
   }
//外面接受返回值
   function num(a,b) {
    return c=a+b;
  }
   var z=num(7,8); //通过=把return的值获取到
   console.log(z); 
  </script> 
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