When the value of String is the same as String.split('') parameter 1 and is not empty, the length of the split array is 2. Use String.substr(1).split('') to split the array. The array length is 1
For example:
let a = ','
a.split(',')
//返回結(jié)果 ["",""], a.length為2
a.substr(1).split(',')
//返回結(jié)果 [""], a.length為1
a = ''
a.split('')
//返回結(jié)果[], a.length為0
1
0
0
小伙看你根骨奇佳，潛力無限，來學(xué)PHP伐。
You don’t understand String.prototype.substr().
a.substr(1) means: starting from index 1 (the second position) and ending at the end of the string.
So what we get here is the null character.
So split did not match and returned itself (empty string).
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