浅析PHP正则表达式定位字符
对于PHP正则表达式定位字符的使用是我们在开发过程中经常会遇到的，那么具体的PHP正则表达式定位字符种类有什么呢？他们具体的代表什么内容呢？让我们开始逐一介绍。
PHP正则表达式定位字符的作用：
PHP正则表达式定位字符是PHP正则表达式中一类非常重要的字符，它的主要作用是用于对字符在匹配对象中的位置进行描述。
PHP正则表达式定位字符的种类及含义：
◆^：
表示匹配的模式出现在匹配对象的开头（和在"[]"里面不同）
◆$：
表示匹配的模式出现在匹配对象的末尾
◆空格：
表示匹配的模式出现在开始和结尾的两个边界之一
◆"/^he/"：
可以匹配以"he"字符开头的字符串，比如hello、height等等；
◆"/he$/"：
可以匹配以"he"字符结尾的字符串即she等；
◆"/ he/"：
空格开头，和^的作用一样，匹配以he开头的字符串；
◆"/he /"：
空格结束，和$的作用一样，匹配以he结尾的字符串；
◆"/^he$/"：
表示只和字符串"he"匹配。
PHP正则表达式定位字符的简单介绍就向你讲述到这里，希望对你了解和掌握PHP正则表达式定位字符有所帮助。
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