PHP string函数总结 PHP string函数总结 ? ================================== ceil、floor、round、/、% ? float ceil ( float $value )向上去整(进一) ??? cout(1.8)=>2??? cout(-1.8)=>2-1 float floor ( float $value )向下去整(舍去)??? floor(1.8)=>1??? floor(-1.8)=>-2 round — 对浮点数进行四舍五入 float round ( float $val [, int $precision ] ) ??? echo?round(1.95583,?2);??//?1.96??? echo?round(1241757,?-3);?//?1242000=================================