I have a JSON output from an HTTP get. I am then using JSON.parse from nodejs.
The output is basically like this:
items: [
snippet: {
foo: "bar",
bar: "foo
}
snippet: {
foo: "bar",
bar: "foo
}
snippet: {
foo: "bar",
bar: "foo
}
]
My code is then as such:
foo1 = items[0].snippet.foo
bar1 = items[0].snippet.bar
this variable declaration all works fine, until I get to the variables that might not exist sometimes.
foo4 = items[4].snippet.foo
Of course, this right here does not exist. I thought that I would be able to simply do an if(foo4 == 'Null') then set foo4 = 'not existing' so it does not crash my program later. However, the program crashes when DECLARING this variable itself... how can I prevent this from happening?
in ES2020 there is cool feature called optional chaining and nullish coalescing , so you can try to combine them:
foo4 = items[4]?.snippet?.foo ?? 'not existing'
So if items[4]
is null or undefined part items[4]?.snippet?.foo
will set undefined to foo4 and then operator ??
will add default value to variable foo 4
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