PHP常用函数

<?php
$a1=array("a"=>"red","b"=>"green","c"=>"blue","d"=>"yellow");
$a2=array("e"=>"red","f"=>"green","g"=>"blue");$result=array_intersect($a1,$a2);
print_r($result);
?>
result:Array ( [a] => red [b] => green [c] => blue )

<?php
$a=array("Volvo"=>"XC90","BMW"=>"X5","Toyota"=>"Highlander");
print_r(array_keys($a));
?>
result:Array ( [0] => Volvo [1] => BMW [2] => Toyota )123456

<?php
    $a=array("Volvo"=>"XC90","BMW"=>"X5");    if (array_key_exists("Volvo",$a))
      {      echo "键存在！";
      }    else
      {      echo "键不存在！";
      }?>
      result:键存在！12345678910111213

<?php
$a1=array("red","green");$a2=array("blue","yellow");
print_r(array_merge($a1,$a2));
?>
result:Array ( [0] => red [1] => green [2] => blue [3] => yellow )1234567

<?php
$a=array("a"=>"Volvo","b"=>"BMW","c"=>"Toyota");
print_r(array_reverse($a));
?>
result:Array ( [c] => Toyota [b] => BMW [a] => Volvo )123456

<?ph
$a=array("a"=>"red","b"=>"green");
array_unshift($a,"blue");
print_r($a);
?>
result:Array ( [0] => blue [a] => red [b] => green )1234567

<?php
$a=array("Name"=>"Bill","Age"=>"60","Country"=>"USA");
print_r(array_values($a));
?>
result:Array ( [0] => Bill [1] => 60 [2] => USA )123456

<?php$expected  = crypt('12345', '$2a$07$usesomesillystringforsalt$');
$correct = crypt('12345', '$2a$07$usesomesillystringforsalt$');
$incorrect = crypt('apple',  '$2a$07$usesomesillystringforsalt$');
var_dump(hash_equals($expected, $correct));
var_dump(hash_equals($expected, $incorrect));
?>
result:
bool(true)
bool(false)123456789101112

<?php$people = array("Bill", "Steve", "Mark", "David");if (in_array("Mark", $people))
  {  echo "匹配已找到";
  }else
  {  echo "匹配未找到";
  }
 ?>
result:匹配已找到1234567891011121314

<?php
$number = 2;
$str = "Shanghai";
$txt = sprintf("There are %u million cars in %s.",$number,$str);
echo $txt;
?>
result:There are 2 million cars in Shanghai.12345678

<?php
echo str_ireplace("WORLD","Shanghai","Hello world!");
?>
result:Hello Shanghai!12345

<?php
echo strpos("You love php, I love php too!","php");
?>
result:912345

<?php
echo str_replace("world","Shanghai","Hello world!");
?>
result:Hello Shanghai!12345

<?php
echo str_ireplace("WORLD","Shanghai","Hello world!");
?>
result:Hello Shanghai!12345

<?php
echo substr("Hello world",6);
?>
result:world