妄徒之命 2010-01-11 23:16 采纳率: 100%
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在 Perl 中,检查字符串是否为空的正确方法是什么?

I've just been using this code to check if a string is empty:

if ($str == "")
{
  // ...
}

And also the same with the not equals operator...

if ($str != "")
{
  // ...
}

This seems to work (I think), but I'm not sure it's the correct way, or if there are any unforeseen drawbacks. Something just doesn't feel right about it.

转载于:https://stackoverflow.com/questions/2045644/what-is-the-proper-way-to-check-if-a-string-is-empty-in-perl

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  • 笑故挽风 2010-01-11 23:20
    关注

    For string comparisons in Perl, use eq or ne:

    if ($str eq "")
    {
      // ...
    }
    

    The == and != operators are numeric comparison operators. They will attempt to convert both operands to integers before comparing them.

    See the perlop man page for more information.

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