function_double.php

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<?php
function Cookie_clear($cookie="double"){
	if ($_COOKIE[$cookie]) {
		setcookie($cookie,"",time()-20,"/");
		$_COOKIE[$cookie]="";
	}	
}

function Cookie_if($msg,$url="javascript:history.back(1)",$cookie="double"){
	if ($_COOKIE[$cookie]) {
		echo "<SCRIPT language=JavaScript>";
		if ($msg<>'') echo "alert(\" 信息：$msg \");";
		echo "window.location='$url';</SCRIPT>";
		exit;
	}else {
		setcookie($cookie,"1",time()+20,"/");
		$_COOKIE[$cookie]=1;
	}
}
?>