AJAX ASP/PHP
AJAX 用於創造動態性更強的應用程序。
AJAX ASP/PHP 實例
下面的例子將為您演示當用戶在輸入框中鍵入字符時，網頁如何與web 服務器進行通信： 請在下面的輸入框中鍵入字母（A - Z）：
實例解析- showHint() 函數
當用戶在上面的輸入框中鍵入字符時，會執行函數"showHint()" 。 該函數由"onkeyup" 事件觸發：
function showHint(str)
{
var xmlhttp;
if (str.length==0)
{
document.getElementById("txtHint").innerHTML="";
return;
}
if (window.XMLHttpRequest)
{// code for IE7+, Firefox, Chrome, Opera, Safari
xmlhttp=new XMLHttpRequest();
}
else
{// code for IE6, IE5
xmlhttp=new ActiveXObject("Microsoft.XMLHTTP");
}
xmlhttp.onreadystatechange=function()
{
if (xmlhttp.readyState==4 && xmlhttp.status==200)
{
document.getElementById("txtHint").innerHTML=xmlhttp.responseText;
}
}
xmlhttp.open("GET","gethint.html?q="+str,true);
xmlhttp.send();
}
{
var xmlhttp;
if (str.length==0)
{
document.getElementById("txtHint").innerHTML="";
return;
}
if (window.XMLHttpRequest)
{// code for IE7+, Firefox, Chrome, Opera, Safari
xmlhttp=new XMLHttpRequest();
}
else
{// code for IE6, IE5
xmlhttp=new ActiveXObject("Microsoft.XMLHTTP");
}
xmlhttp.onreadystatechange=function()
{
if (xmlhttp.readyState==4 && xmlhttp.status==200)
{
document.getElementById("txtHint").innerHTML=xmlhttp.responseText;
}
}
xmlhttp.open("GET","gethint.html?q="+str,true);
xmlhttp.send();
}
源代碼解析：
如果輸入框為空(str.length==0)，則該函數清空txtHint 佔位符的內容，並退出函數。
如果輸入框不為空，showHint() 函數執行以下任務：
- 創建XMLHttpRequest 對象
- 當服務器響應就緒時執行函數
- 把請求發送到服務器上的文件
- 請注意我們向URL 添加了一個參數q （帶有輸入框的內容）
AJAX 服務器頁面- ASP 和PHP
由上面的JavaScript 調用的服務器頁面是ASP 文件，名為"gethint.asp"。
下面，我們創建了兩個版本的服務器文件，一個用ASP 編寫，另一個用PHP 編寫。
ASP 文件
"gethint.asp" 中的源代碼會檢查一個名字數組，然後向瀏覽器返回相應的名字：
<%
response.expires=-1
dim a(30)
'Fill up array with names
a(1)="Anna"
a(2)="Brittany"
a(3)="Cinderella"
a(4)="Diana"
a(5)="Eva"
a(6)="Fiona"
a(7)="Gunda"
a(8)="Hege"
a(9)="Inga"
a(10)="Johanna"
a(11)="Kitty"
a(12)="Linda"
a(13)="Nina"
a(14)="Ophelia"
a(15)="Petunia"
a(16)="Amanda"
a(17)="Raquel"
a(18)="Cindy"
a(19)="Doris"
a(20)="Eve"
a(21)="Evita"
a(22)="Sunniva"
a(23)="Tove"
a(24)="Unni"
a(25)="Violet"
a(26)="Liza"
a(27)="Elizabeth"
a(28)="Ellen"
a(29)="Wenche"
a(30)="Vicky"
'get the q parameter from URL
q=ucase(request.querystring("q"))
'lookup all hints from array if length of q>0
if len(q)>0 then
hint=""
for i=1 to 30
if q=ucase(mid(a(i),1,len(q))) then
if hint="" then
hint=a(i)
else
hint=hint & " , " & a(i)
end if
end if
next
end if
'Output "no suggestion" if no hint were found
'or output the correct values
if hint="" then
response.write("no suggestion")
else
response.write(hint)
end if
%>
response.expires=-1
dim a(30)
'Fill up array with names
a(1)="Anna"
a(2)="Brittany"
a(3)="Cinderella"
a(4)="Diana"
a(5)="Eva"
a(6)="Fiona"
a(7)="Gunda"
a(8)="Hege"
a(9)="Inga"
a(10)="Johanna"
a(11)="Kitty"
a(12)="Linda"
a(13)="Nina"
a(14)="Ophelia"
a(15)="Petunia"
a(16)="Amanda"
a(17)="Raquel"
a(18)="Cindy"
a(19)="Doris"
a(20)="Eve"
a(21)="Evita"
a(22)="Sunniva"
a(23)="Tove"
a(24)="Unni"
a(25)="Violet"
a(26)="Liza"
a(27)="Elizabeth"
a(28)="Ellen"
a(29)="Wenche"
a(30)="Vicky"
'get the q parameter from URL
q=ucase(request.querystring("q"))
'lookup all hints from array if length of q>0
if len(q)>0 then
hint=""
for i=1 to 30
if q=ucase(mid(a(i),1,len(q))) then
if hint="" then
hint=a(i)
else
hint=hint & " , " & a(i)
end if
end if
next
end if
'Output "no suggestion" if no hint were found
'or output the correct values
if hint="" then
response.write("no suggestion")
else
response.write(hint)
end if
%>
PHP 文件
下面的代碼用PHP 編寫，與上面的ASP 代碼作用是一樣的。
<?php
// Fill up array with names
$a[]="Anna";
$a[]="Brittany";
$a[]="Cinderella";
$a[]="Diana";
$a[]="Eva";
$a[]="Fiona";
$a[]="Gunda";
$a[]="Hege";
$a[]="Inga";
$a[]="Johanna";
$a[]="Kitty";
$a[]="Linda";
$a[]="Nina";
$a[]="Ophelia";
$a[]="Petunia";
$a[]="Amanda";
$a[]="Raquel";
$a[]="Cindy";
$a[]="Doris";
$a[]="Eve";
$a[]="Evita";
$a[]="Sunniva";
$a[]="Tove";
$a[]="Unni";
$a[]="Violet";
$a[]="Liza";
$a[]="Elizabeth";
$a[]="Ellen";
$a[]="Wenche";
$a[]="Vicky";
//get the q parameter from URL
$q=$_GET["q"];
//lookup all hints from array if length of q>0
if (strlen($q) > 0)
{
$hint="";
for($i=0; $i<count($a); $i++)
{
if (strtolower($q)==strtolower(substr($a[$i],0,strlen($q))))
{
if ($hint=="")
{
$hint=$a[$i];
}
else
{
$hint=$hint." , ".$a[$i];
}
}
}
}
// Set output to "no suggestion" if no hint were found
// or to the correct values
if ($hint == "")
{
$response="no suggestion";
}
else
{
$response=$hint;
}
//output the response
echo $response;
?>
// Fill up array with names
$a[]="Anna";
$a[]="Brittany";
$a[]="Cinderella";
$a[]="Diana";
$a[]="Eva";
$a[]="Fiona";
$a[]="Gunda";
$a[]="Hege";
$a[]="Inga";
$a[]="Johanna";
$a[]="Kitty";
$a[]="Linda";
$a[]="Nina";
$a[]="Ophelia";
$a[]="Petunia";
$a[]="Amanda";
$a[]="Raquel";
$a[]="Cindy";
$a[]="Doris";
$a[]="Eve";
$a[]="Evita";
$a[]="Sunniva";
$a[]="Tove";
$a[]="Unni";
$a[]="Violet";
$a[]="Liza";
$a[]="Elizabeth";
$a[]="Ellen";
$a[]="Wenche";
$a[]="Vicky";
//get the q parameter from URL
$q=$_GET["q"];
//lookup all hints from array if length of q>0
if (strlen($q) > 0)
{
$hint="";
for($i=0; $i<count($a); $i++)
{
if (strtolower($q)==strtolower(substr($a[$i],0,strlen($q))))
{
if ($hint=="")
{
$hint=$a[$i];
}
else
{
$hint=$hint." , ".$a[$i];
}
}
}
}
// Set output to "no suggestion" if no hint were found
// or to the correct values
if ($hint == "")
{
$response="no suggestion";
}
else
{
$response=$hint;
}
//output the response
echo $response;
?>