1、统计一段代码运行时间
console.time('total time: ');
for(let i=0;i<1000;i++){
console.log(i);
}
console.timeEnd('total time: ');
2、setTimeout
setTimeout((param)=>{
console.log('set timeout...:'+param);
},1000,'test param');
let start=Date.now();
setTimeout(()=>{
console.log(Date.now()-start);
},1000);
3、sleep
console.log('start');
sleep(2000);
console.log('end');
function sleep(ms){
let start=Date.now();
while(Date.now()-start<ms) {}
}
function sleep(ms){
let start=Date.now();
while(Date.now()-start<ms) {}
}
console.log(new Date().getSeconds());
sleep(1000*3);
console.log(new Date().getSeconds());