const a = null try { const b = JSON.parse(a) console.log(a.name) } catch (e) { console.log("发生异常:" + e) }
这个是系统抛出的异常
下面这个是自定义的异常
·const a = 1
·try {
···if (a == 2 || a == 3) {
···throw 'hahaha'
·} else {
···console.log(a)
··}
·} catch (e) {
···console.log("发生异常:" + e)
·}
throw 得内容会在catch里面返回出来 也类似于return