index.php 內容
大概流程就是
First name: <input type="text" onkeyup="showHint(this.value)">
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function showHint(str)
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xmlhttp.open("GET", "gethint.php?q=" + str, true);
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document.getElementById("txtHint").innerHTML = xmlhttp.responseText;
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<p>Suggestions: <span id="txtHint"></span></p>
文字筆記如下:
<p>Suggestions: <span id="txtHint"></span></p> ->
他內嵌了一段 javascript.... 以 <script> 開頭...
</script> 結尾....
裡面的實作是一個 function showHint(str)
先判斷 str.length 的數值...如果為零...就直接返回空字串....
如果不為零.... 首先取得 xmlhttp = XMLHttpRequest()...
然後check xmlhttp.onreaystatechange ....
如果 xmlhttp.readyState == 4 而且 xmlhttp.status == 200
則 document.getElementById("txtHint").innerHTML = xmlhttp.responseText
"txtHint" 為 html 主體裡面的 <p>Suggestions: <span id="txtHint"></span></p>
接下來執行
xmlhttp.open("GET", "gethint.php?q=" + str, true);
xmlhttp.send();
他會去執行 gethint.php 裡面的程式碼...
$a[] = "Anna";
$a[] = "Brittany";
$a[] = "Cinderella";
........
// get the q parameter from URL
$q = $_REQUEST["q"];
// lookup all hints from array if $q is different from ""
if ($q !== "") {
$q = strtolower($q);
$len=strlen($q);
foreach($a as $name) {
if (stristr($q, substr($name, 0, $len))) {
if ($hint === "") {
$hint = $name;
} else {
$hint .= ", $name";
}
}
}
}
=======================================================
<html>
<head>
<script>
function showHint(str) {
if (str.length == 0) {
document.getElementById("txtHint").innerHTML = "";
return;
} else {
var xmlhttp = new XMLHttpRequest();
xmlhttp.onreadystatechange = function() {
if (xmlhttp.readyState == 4 && xmlhttp.status == 200) {
document.getElementById("txtHint").innerHTML = xmlhttp.responseText;
}
};
xmlhttp.open("GET", "gethint.php?q=" + str, true);
xmlhttp.send();
}
}
</script>
</head>
<body>
<p><b>Start typing a name in the input field below:</b></p>
<form>
First name: <input type="text" onkeyup="showHint(this.value)">
</form>
<p>Suggestions: <span id="txtHint"></span></p>
</body>
</html>
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gethink,php 的內容
=================================================================
<?php
// 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 = $_REQUEST["q"];
$hint = "";
// lookup all hints from array if $q is different from ""
if ($q !== "") {
$q = strtolower($q);
$len=strlen($q);
foreach($a as $name) {
if (stristr($q, substr($name, 0, $len))) {
if ($hint === "") {
$hint = $name;
} else {
$hint .= ", $name";
}
}
}
}
// Output "no suggestion" if no hint was found or output correct values
echo $hint === "" ? "no suggestion" : $hint;
?>
=====================================================================
Reference : http://www.w3schools.com/php/php_ajax_php.asp
