php字符串中查找字符
本文章要讲到的是利用strstr和strpos函数来查询指定字符串中是否有我们想的字符内容,有需要的可以参考一下。
strstr()函数用于获取一个指定字符串在另一个字符串中首次出现的位置到后者末尾的子字符串,如果执行成功,则返回剩余字符串(存在相匹配的字符);如果没有找到相匹配的字符,则返回false。
语法:
string strstr(string haystack,string needle)
参数haystack:必要参数,指定从哪个字符串中进行搜索。
参数needle:必要参数,指定搜索的对象。如果该参数是一个数值,那么将搜索与这个数值的ASCII值相匹配的字符。
实例:
代码如下 | 复制代码 |
echo strstr(“明日编程词典”,”编”); //输出查询的字符串 echo “ ”; //执行回车 echo strstr(“www.111c.net”,”111”); //输出查询的字符串(从第一个m取值) echo “ ”; //执行回车 echo strstr(“0431-84972266″,”8″); //输出查询的字符串 ?> |
定义和用法
strpos() 函数返回字符串在另一个字符串中第一次出现的位置。
如果没有找到该字符串,则返回 false。
语法
strpos(string,find,start)参数 描述
string 必需。规定被搜索的字符串。
find 必需。规定要查找的字符。
start 可选。规定开始搜索的位置。
提示和注释
注释:该函数对大小写敏感。如需进行对大小写不敏感的搜索,请使用 stripos() 函数。
例子
代码如下 | 复制代码 |
echo strpos("Hello world!","wo"); 6 |

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