I output the f here twice, why col only outputs it once! Ask for answers
I output the f here twice, why col only outputs it once! Ask for answers
feel that your writing is wrong, try this way:
columns.map((f,i) => {
console.log('f',f);
f.map((item.index) => {
const col = {
title: this.renderColumnTitle(f),
dataIndex: 'column' + index,
key: item._ref,
};
console.log('col',col);
})
})f is an array? Didn't he just output once?
is output only once. The 2 you see is length
f is just an item in columns . You should take a look at the data structure of columns .
where can I see the output twice.
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