encountered such a problem, mainly due to the data returned by the ajax request.
:
res = {
other:"",
list: [
{
a:1,
b:{},
c:[
{
d:1
e:2
}
]
}
]
}
,, null,,,null,
c.map,
res.list && res.list.length && c.map(item=>(
item.c && item.c.length <div>
))
res.list && res.list.length &&
jsx,,
generally judge whether the request is successful or not, and then determine whether the data in the request exists
optional-chaining is recommended. https://github.com/tc39/propo.
res?.list?.c.map(item=>(
//
))official plug-in implementation of babel: https://github.com/babel/babe.
another way is to use the proxy proxy. Here is a proxy implementation: https://gist.github.com/zenpa.
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