Async and await

async function

• The return value of the function is promise object
• promise The result of the object is determined by async The return value of the function execution determines

await expression

• await The expression on the right is usually promise object , But it can be something else
• If the expression is promise object , await The return is promise The value of success
• If the expression is another value , Take this value directly as await The return value of

Be careful

• await Must be written in async Function , but async There can be no await
• If await Of promise failed , Will throw an exception , Need to pass through try...catch Capture processing

Because I am not particularly good at front-end learning , So it's about async And await See the link below for more information ,

async and await（ Detailed explanation ）_ A blog destined to learn to dominate life -CSDN Blog _async and await Detailed explanation https://blog.csdn.net/qq_40282016/article/details/118461230?ops_request_misc=%257B%2522request%255Fid%2522%253A%2522165493231716781683940327%2522%252C%2522scm%2522%253A%252220140713.130102334..%2522%257D&request_id=165493231716781683940327&biz_id=0&utm_medium=distribute.pc_search_result.none-task-blog-2~all~sobaiduend~default-1-118461230-null-null.142^v13^control,157^v14^control&utm_term=async+%E4%B8%8E+await&spm=1018.2226.3001.4187