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<?php
//µ÷ÓôËÒ³Ã棬Èç¹ûÏÂÃæµÄʽ×Ó³ÉÁ¢£¬ÔòÉú³ÉÑéÖ¤ÂëͼƬ
if($_GET["action"]=="verifycode")
{
    rand_create();
}
//ÑéÖ¤ÂëͼƬÉú³É
function rand_create()
{
    //֪ͨä¯ÀÀÆ÷½«ÒªÊä³öPNGͼƬ
    Header("Content-type: image/PNG");
    //×¼±¸ºÃËæ»úÊý·¢ÉúÆ÷ÖÖ×Ó
    srand((double)microtime()*1000000);
    //×¼±¸Í¼Æ¬µÄÏà¹Ø²ÎÊý 
    $im = imagecreate(62,20);
    $black = ImageColorAllocate($im, 0,0,0);  //RGBºÚÉ«±êʶ·û
    $white = ImageColorAllocate($im, 255,255,255); //RGB°×É«±êʶ·û
    $gray = ImageColorAllocate($im, 200,200,200); //RGB»ÒÉ«±êʶ·û
    //¿ªÊ¼×÷ͼ   
    imagefill($im,0,0,$gray);
    while(($randval=rand()%100000)<10000);{
        $_SESSION["login_check_num"] = $randval;
        //½«ËÄλÕûÊýÑéÖ¤Âë»æÈëͼƬ
        imagestring($im, 5, 10, 3, $randval, $black);
    }
    //¼ÓÈë¸ÉÈÅÏóËØ  
    for($i=0;$i<200;$i++){
        $randcolor = ImageColorallocate($im,rand(0,255),rand(0,255),rand(0,255));
        imagesetpixel($im, rand()%70 , rand()%30 , $randcolor);
    }
    //Êä³öÑé֤ͼƬ
    ImagePNG($im);
    //Ïú»ÙͼÏñ±êʶ·û
    ImageDestroy($im);
}
//¼ìÑéÑéÖ¤Âë
function rand_check()
{
    if($_POST["reg_rand"] == $_SE