function
createxhr(){
if
(window.XMLHttpRequest){
var
xhr =
new
XMLHttpRequest();
}
else
{
var
version = [
"Msxml2.XMLHTTP.6.0"
,
"Msxml2.XMLHTTP.5.0"
,
"Msxml2.XMLHTTP.4.0"
,
"Msxml2.XMLHTTP.3.0"
,
"Msxml2.XMLHTTP"
,
"Microsoft.XMLHTTP"
];
for
(
var
i=0,len=version.length; i<len; i++){
var
xhr =
new
ActiveXObject(version[i]);
if
(xhr){
break
;
}
}
}
return
xhr;
}
function
$(id){
return
document.getElementById(id);
}
window.onload =
function
() {
$(
'username'
).onblur =
function
(){
var
name = $(
'username'
).value;
var
xhr = createxhr();
xhr.onreadystatechange =
function
(){
if
(xhr.readyState == 4 ){
var
res = $(
'res'
);
res.innerHTML = xhr.responseText;
}
}
xhr.open(
'get'
,
'./data.php?username='
+name,
true
);
xhr.send(
null
);
}
}
代码][JavaScript]代码
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$link = mysql_connect( '127.0.0.1' , 'root' , 'slops' );
mysql_select_db( 'test' );
mysql_query( 'set names utf8' ,$link);
$username = $_GET[ 'username' ];
if (!empty($username)){
$sql = "select * from user where username ='$username'" ;
$res = mysql_query($sql);
$result = mysql_num_rows($res);
if ($result>0){
echo "该用户已存在,请从新选择用户名!!!" .$username;
}
else {
echo "恭喜你,可以注册" .$username;
}
} else {
echo "用户名不能为空" ;
}
mysql_close();
|