[PHP知识库]PHP函数version_compare

version_compare比较php的版本

/**
 * Compares two "PHP-standardized" version number strings
 * @link https://php.net/manual/en/function.version-compare.php
 * @param string $version1 <p>
 * First version number.
 * </p>
 * @param string $version2 <p>
 * Second version number.
 * </p>
 * @param string $operator [optional] <p>
 * If you specify the third optional operator
 * argument, you can test for a particular relationship. The
 * possible operators are: &lt;,
 * lt, &lt;=,
 * le, &gt;,
 * gt, &gt;=,
 * ge, ==,
 * =, eq,
 * !=, &lt;&gt;,
 * ne respectively.
 * </p>
 * <p>
 * This parameter is case-sensitive, so values should be lowercase.
 * </p>
 * @return int|bool By default, version_compare returns
 * -1 if the first version is lower than the second,
 * 0 if they are equal, and
 * 1 if the second is lower.
 * </p>
 * <p>
 * When using the optional operator argument, the
 * function will return true if the relationship is the one specified
 * by the operator, false otherwise.
 */
function version_compare($version1, $version2, $operator = null) { }

示例：

var_dump(PHP_VERSION);//string(5) "7.3.4"

$result = version_compare('7.3.0', PHP_VERSION, '<');
var_dump($result);//bool(true)

$result = version_compare('7.3.0', PHP_VERSION, '>');
var_dump($result);//bool(false)