PHP ，多维数组转换字符串，字符串转换数组（多维数组）

<?/*在Array和String类型之间转换，转换为字符串的数组可以直接在URL上传递*/
// convert a multidimensional array to url save and encoded string
// usage: string Array2String( array Array )
function Array2String($Array)
{
    $Return='';
    $NullValue="^^^";
    foreach ($Array as $Key => $Value) {
        if(is_array($Value))
            $ReturnValue='^^array^'.Array2String($Value);
        else
            $ReturnValue=(strlen($Value)>0)?$Value:$NullValue;
        $Return.=urlencode(base64_encode($Key)) . '|' . urlencode(base64_encode($ReturnValue)).'||';
    }
    return urlencode(substr($Return,0,-2));
}
// convert a string generated with Array2String() back to the original (multidimensional) array
// usage: array String2Array ( string String)
function String2Array($String)
{
    $Return=array();
    $String=urldecode($String);
    $TempArray=explode('||',$String);
    $NullValue=urlencode(base64_encode("^^^"));
    foreach ($TempArray as $TempValue) {
        list($Key,$Value)=explode('|',$TempValue);
        $DecodedKey=base64_decode(urldecode($Key));
        if($Value!=$NullValue) {
            $ReturnValue=base64_decode(urldecode($Value));
            if(substr($ReturnValue,0,8)=='^^array^')
                $ReturnValue=String2Array(substr($ReturnValue,8));
            $Return[$DecodedKey]=$ReturnValue;
        }
        else
        $Return[$DecodedKey]=NULL;
    }
    return $Return;
}
?>