strpos：指定した文字列が最初に現れる位置を調べる

<?php $str1 = "HAGE HIGE HOGE"; echo strpos( $str1, "HAGE" ) . "\n";//0 echo strpos( $str1, "HIGE" ) . "\n";//5 echo strpos( $str1, "HOGE" ) . "\n";//10 echo strpos( $str1, "IG" ) . "\n";//6 echo strpos( $str1, "NG" ) . "\n";//false echo strpos( $str1, "HAGE", 3 ) . "\n";//false echo strpos( $str1, "HIGE", 3 ) . "\n";//5 echo strpos( $str1, "HOGE", 3 ) . "\n";//10 echo strpos( $str1, "IG" , 3 ) .