如何编写一个 php 函数，输入是数组并且函数找到最小的数字

此函数做了一些假设，例如传入的值实际上是一个包含一些值的数组。如果您愿意，您可以为此添加一些验证...

function findLowest($myArray)
{
    $currLowest=$myArray[0];
    foreach($myArray as $val)
    {
        if($val < $currLowest)
        {
            $currLowest=$val;
        }
    }
    return $currLowest;
}

内置函数或自定义函数来实现

$numbers=array( 4 => 40, 3 => 30, 13 => 38 );
function getMin($source = array())
{
 //If you don't need your original index for the lowest value  
   sort($source);
 // after sort original index is lost.
   return $source[0]
 //OR
//If you need your original index for the lowest value  
   asort($source);
   foreach($source as $key => $value)
   {
       return $value; //ie return key or value that you need.
   }
}

使用函数中的任何一个逻辑。

$numbers=array( 4 => 40, 3 => 30, 13 => 38 );
function getMin($source = array())
{
 //If you don't need your original index for the lowest value  
   sort($source);
 // after sort original index is lost.
   return $source[0]
 //OR
//If you need your original index for the lowest value  
   asort($source);
   foreach($source as $key => $value)
   {
       return $value; //ie return key or value that you need.
   }
}

这对我有帮助。:)