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javascriptjqueryparseint

String To Number Confusion

Why does parseInt("-1000-500-75-33") return -1000?

Shouldn't it return the sum of those numbers: -1608

How can I get the string "-1000-500-75-33" to return as the sum of those numbers?

Solution

  • parseInt will try to get a number starting from the beginning of the string.

    Since - is a valid character to begin a number with, it parses the string until it finds something invalid. The second - is invalid because no integer can contain an - inside it, only digits. So it stops there and considers the number to be "finished".

    Now, if you want to process the expression, you can use eval like so:

    eval("-1000-500-75-33")

    This will return -1608 as expected.