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
??? 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
??? echo? round ( 1241757 ,?- 3 );? //?1242000
=================================