php获取当前网址url并替换参数或网址的方法

//获得当前的脚本网址
function GetCurUrl()
{
if(!empty($_SERVER["REQUEST_URI"]))
{
$scriptName = $_SERVER["REQUEST_URI"];
$nowurl = $scriptName;
}
else
{
$scriptName = $_SERVER["PHP_SELF"];
if(empty($_SERVER["QUERY_STRING"]))
{
$nowurl = $scriptName;
}
else
{
$nowurl = $scriptName."?".$_SERVER["QUERY_STRING"];
}
}
return $nowurl;
}

/* 将URL中的某参数设为某值*/ //【这一段就挺好啊】
function url_set_value($url,$key,$value)
{
$a=explode(?,$url);
$url_f=$a[0];
$query=$a[1];
parse_str($query,$arr);
$arr[$key]=$value;
return $url_f.?.http_build_query($arr);
}

<?php
/**
*使用例程：可用于分页类或页面中的替换等
$url = "add_jd.php?pid=4&tb=gm_jd&page=1";
echo( "原始的URL：" . $url );
echo( <br/> );
echo( "字符串参数：" . url::replace( $url , "pid=10,page=2") );
echo( <br/> );
echo( "数组型参数：" . url::replace( $url , array(pid=>10,page=>5)) );
//echo( urlReplace( $url , array(pid=>10,page=>5)) );
*/
/**
* url replace
* @param string $url 需要替换的URL字符串，一般为aaa.php?abc=def,也可以带上路径，象http://xxx.com/abc/def.php?aa=bb
* @param mixed $options 需要替换的变量，可以是字符串或数组，如果是字符串，格式为"aa=bb,cc=dd"，有多个，用","隔开
* @return string $url 替换后的URL
*/
class url
{
static function replace ( $url , $options)
{
$options = self::optInit( $options );
$Query = parse_url( $url , PHP_URL_QUERY );
if($Query){
parse_str( $Query , $GET );
if ( $GET ){
//foreach ( $GET as $_k => $_v ){
// //if( array_key_exists( $_k , $options)){
// $GET[$_k] = $options[$_k];
// //}
//}
$GET = array_merge($GET,$options);
}
return str_replace( $Query , http_build_query( $GET ), $url );
}
if( !$Query && $options ){
return $url . "?" . http_build_query($options);
}
return $url;
}
static private function optInit ( $options )
{
if( is_string( $options )){
$optlists = Power::Normalize( $options );
foreach( $optlists as $val){
list($tmpKey,$tmpVal) = Power::Normalize( $val , "=");
$opts[$tmpKey] = $tmpVal;
}
}else{
$opts = $options;
}
//unset( $options );
return $opts;
}
}