正题1、1varlength=1;2functionfn(){3console.log(this.length);4}5varobj={6length:100,7action:function(callback){8callback();9arguments[0]();10}11}12obj.action(fn,...[1,2,3,4]);2、1vara=10;2functiontest(){3console.log(a);4a=100;5console.log(this.a);6vara;7console.log(a);8}9test();3、1vara=10;2functionf1(){3