PHP (20140507)

Through Ajax to the database to verify the existence of this user:

PHP Code:

1<?PHP2 if(isset($_get[' User '])){3     $user=$_get[' User '];4     include("util.php");5     $sql= "SELECT count (*) from ' username ' where sname = '$user‘";6     $result=mysql_query($sql);7     $row=Mysql_fetch_row($result);9     if($row[0]){Ten         Echo"The user has already been registered!" "; One}Else { A         Echo"The user has not been used and can register!" "; -     } - } the  -?>

JS Code:

1 varxmlHttp;2 functiongetxmlhttp () {3     if(window. ActiveXObject) {4XmlHttp =NewActiveXObject ("MICROSOFT. XMLHTTP ");5}Else if(window. XMLHttpRequest) {6XmlHttp =NewXMLHttpRequest ();7     }8 }9 functionsendparam (URL) {Ten getxmlhttp (); OneXmlhttp.open ("GET", "register.php?user=" +url,true); AXmlhttp.onreadystatechange =Gettxt; -Xmlhttp.send (NULL); - } the functionGettxt () { -     if(Xmlhttp.readystate = = 4){ -         if(Xmlhttp.status = = 200){ -             varSP = document.getElementById ("Tishi"); +sp.innerhtml =Xmlhttp.responsetext; -         } +     } A}

HTML code:

1 <formMethod= "POST"Action= "register.php">2User:<inputclass= "INP"onblur= "Sendparam (this.value)"type= "text"name= "User">3             <spanstyle= "color: #ff0000; font-size:16px"ID= "Tishi"></span>  <BR> <BR>4Password:<inputclass= "INP"type= "Password"name= "pwd"><span></span>5             <inputID= "CE"type= "Submit"name= "Submit"value= "Register">6         </form>