PHP的问题:strpos功能不起作用 [英] php problem: strpos function not working

问题描述

为什么以下php代码不起作用:

why is the following php code not working:

$string = "123";
$search = "123";

if(strpos($string,$search))
{
    echo "found";
}else{
    echo "not found";
}

由于$ search在$ string中-不应按找到的方式触发它?

as $search is in $string - shouldn't it be triggered as found?

推荐答案

这在手册:strpos()

此函数可以返回布尔FALSE，但也可以返回非布尔值，其值为FALSE，例如0或".请阅读有关布尔值的部分以了解更多信息.使用===运算符测试此函数的返回值.

This function may return Boolean FALSE, but may also return a non-Boolean value which evaluates to FALSE, such as 0 or "". Please read the section on Booleans for more information. Use the === operator for testing the return value of this function.

在您的情况下，该字符串位于索引0和php 0 == false

In your case the string is found at the index 0 and in php 0 == false

解决方案是只使用严格的比较器

The solution is to just use the strict comparator

echo strpos($string,$search) === false
     ? "not found"
     : "found";

另一个

echo is_int(strpos($string,$search))
     ? "found"
     : "not found";

或者某事...让我们说些有趣的:D仅用于说明.我不推荐这个.

Or something ... lets say interesting :D Just for illustration. I don't recommend this one.

echo strpos('_' . $string,$search) // we just shift the string 1 to the right
     ? "found"
     : "not found";

这篇关于PHP的问题:strpos功能不起作用的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！