JS 中try用法

const a = null

try {
    const b = JSON.parse(a)
    console.log(a.name)
} catch (e) {
    console.log("發生異常:" + e)
}
這個是系統拋出的異常

下面這個是自定義的異常

·const a = 1

·try {
···if (a == 2 || a == 3) {
···throw 'hahaha'
·} else {
···console.log(a)
··}
·} catch (e) {
···console.log("發生異常:" + e)
·}

 

 throw 得內容會在catch里面返回出來 也類似於return