它不是ug,而是feature。 任何扼杀均可投给愤怒者,但。 如果扼杀物没有开始产生分类值,则投放器将返回。 此外,在比较愤怒和扼杀时,strcmp,因为它通过将任何东西传递给扼杀,进行了明确的描述性比较。)

为保证处理星体的Im,我将首先使用is_vidic ,然后将体格转换为int,并核实所加固的物体与投入价值相符。

if (is_numeric($value) && strcmp((int)$value, $value) == 0)
{
    // $value is an integer value represented as a string
}

http://php.net/manual/en/English.operators.comparison.php rel=“nofollow”http://php.net/manual/en/English.operators.comparison.php:

var_dump(0 == "a"); // 0 == 0 -> true

因此,我认为,它正在计算这些类型,实际上使双方陷入困境。 然后,在插图中,将二元数值或各指数的二元数值加以比较。

首先,数学=中转/c(A=B和B=C=>A=C)有效。

This is not the case with PHPs "=="!

(int)$var1 == $var1

在这种情况下,PHP将引伸到0号——该公约。

然后 = 操作器将含蓄地将第二部操作体也投放到星体——和0。

这导致这种情况。

你与你的职位相差错,正确的产出是:

bool(true)
bool(true)
int(0)
string(6) "string"

What happens is this:

1. Because you cast the variable to an integer, and you compare it to an integer with a loose comparison ==, PHP will first implicitely cast the string to an integer, a more explicit but 100% equivalent form would be: if((int)$var1 == (int) $var1)
2. See 1), the same thing applies here
3. It prints int(0), as it should, because it fails to parse the number, it will return 0 instead.
4. Prints string(6) "string" - as expected

<>说明: 回答是。 有关Twig模板发动机的相关问题,该模板被标为重复,此处改头。

Because the context is different, this answer is provided to those members of the SO community who may benefit from additional details specifically related to twig exclusively.

TL;DR: see this post How do the PHP equality (== double equals) and identity (=== triple equals) comparison operators differ?

Problem

Context

• Twig template engine (latest version as of Fri 2017-01-27T05:12:25)

Scenario

• DeveloperYlohEnrohK uses comparison operator in twig expression
• DeveloperYlohEnrohK notices unexpected results when using equality comparison operator

Questions

• Why does the equality comparison operator (==) produce unexpected results in Twig?

• 以下各点是否产生了不同的结果?

  {{ dump(0 ==  somekey ) }}          ==> true
  {{ dump(0|lower ==  somekey ) }}    ==> false
  

Solution

• Since Twig is based on PHP, the casting, implicit type-conversion and comparison semantics of PHP apply to Twig templates as well.
• Unless DeveloperYlohEnrohK is intentionally and specifically leveraging the behavior of implicit type-conversion in PHP, the comparison expression will almost certainly produce counterintuitive and unexpected results.
• This is a well-known circumstance that is described in detail in this SO post on PHP equality.
• Solution: Just as is the case with standard PHP, unless the well-known circumstance is accounted for, using === in Twig is much less likely to produce unexpected results.

Pitfalls

• As of this writing, the Twig template engine does not support === in the same way as standard PHP
• Twig does have a substitute for === using same as
• Because of this, the treatment of this well-known circumstance differs slightly between PHP and Twig.

See also

• How do the PHP equality (== double equals) and identity (=== triple equals) comparison operators differ?
• http://twig.sensiolabs.org/doc/2.x/tests/sameas.html

如果你想要比较变量类型,那么你也应使用=。

这里的职能是更严格地检测胎体或机体。

function isIntegerNumeric($val) {
  return (
    is_int($val)
      || (
        !is_float($val)
          && is_numeric($val)
          && strpos($val, ".") === false
      )
  );
}

它相对较快,避免进行任何严格检查。