, H5 l; Z* _' _ `4 j- G( ?5. console.time()和console.timeEnd()! n# K. {& H$ w# `) D
无论何时我们想知道一段代码或一个函数所需要花费的时间,都可以使用JavaScript控制台对象提供的time()和timeEnd()方法。关键是要有一个必须相同的标签,而里面的代码可以是任何东西(函数、对象、甚至直接console.log()都可以)。8 d5 t3 k+ r8 K T6 D9 D2 N. z
// console.time() and console.timeEnd() method
// console.time() method
console.time("Let's see time console")
let time1 = function(){
console.log('time1 function is running')
}
let time2 = function(){
console.log('time2 function is running')
}
time1()
time2()
// console.timeEnd() method
console.timeEnd('Time Taken')
# Q8 q: D: |1 {0 E, T: ]+ Z 6. console.table()5 g$ z+ U2 b. B% H4 p# Y" D' a
这个方法允许我们在控制台中生成表格。输入数据必须是数组或显示为表格的对象。6 t9 z, h! T) Y
// console.group() and console.groupEnd() method
// console.group() method
console.group('This is a sample group')
console.log('This is a sample group log')
console.warn('This is a sample group warning')
console.error('This is a sample group error')
// console.groupEnd() method
console.groupEnd('This is a sample group')
console.log('This is a new section')