我正在开发一个元搜索引擎网站Soogle,我已经使用JS来填充选择菜单..
现在,在加载页面后,默认情况下没有加载任何引擎,用户需要自己选择它或[TAB]来选择..
是否有可能在页面加载后通过JS从菜单中预选一个值?
这是代码:
使用Javascript:
// SEARCH FORM INIT
function addOptions(){
var sel=document.searchForm.whichEngine;
for(var i=0,l=arr.length;i<l;i++){
sel.options[i]=new Option(arr[i][0], i);
}
}
function startSearch(){
var searchString=document.searchForm.searchText.value;
if(searchString.replace(/\s+/g,"").length > 0){
var searchEngine=document.searchForm.whichEngine.selectedIndex,
finalSearchString=arr[searchEngine][1]+searchString;
window.location=finalSearchString;
}
return false;
}
function checkKey(e){
var key = e.which ? e.which : event.keyCode;
if(key === 13){
return startSearch();
}
}
// SEARCH ENGINES INIT
var arr = [
["Web", "http://www.google.com/search?q="],
["Images", "http://images.google.com/images?q="],
["Knowledge","http://en.wikipedia.org/wiki/Special:Search?search="],
["Videos","http://www.youtube.com/results?search_query="],
["Movies", "http://www.imdb.com/find?q="],
["Torrents", "http://thepiratebay.org/search/"]
];
HTML:
<body onload="addOptions();document.forms.searchForm.searchText.focus()">
<div id="wrapper">
<div id="logo"></div>
<form name="searchForm" method="POST" action="javascript:void(0)">
<input name="searchText" type="text" onkeypress="checkKey(event);"/>
<span id="color"></span>
<select tabindex="1" name="whichEngine" selected="Web"></select>
<br />
<input tabindex="2" type="button" onClick="return startSearch()" value="Search"/>
</form>
</div>
</body>
答案 0 :(得分:5)
我感谢你的问题要求使用JavaScript的解决方案,但是看了有问题的网页我对这一点有信心:
您的问题是,您正在尝试将JavaScript用于HTML本身旨在解决的问题:
<select name="whichEngine">
<option value="http://www.google.com/search?q=" selected="selected">Web</option>
<option value="http://images.google.com/images?q=">Images</option>
<option value="http://en.wikipedia.org/wiki/Special:Search?search=">Knowledge</option>
<option value="http://www.youtube.com/results?search_query=">Videos</option>
<option value="http://www.imdb.com/find?q=">Movies</option>
<option value="http://thepiratebay.org/search/">Torrents</option>
</select>
不要害怕!您仍然可以像以前一样访问JavaScript中的所有选项。
function alertSelectedEngine() {
var e = document.getElementsByName("whichEngine")[0];
alert("The user has selected: "+e.options[e.selectedIndex].text+" ("+e.options[e.selectedIndex].value+")");
}
请原谅并听取我的意见。
答案 1 :(得分:2)
我修改了代码以使用jQuery。它在IE8,IE8(兼容模式)和FireFox中运行良好。
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
<head id="Head1" runat="server">
<title>Index</title>
<script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.4.2/jquery.min.js"></script>
<script type="text/javascript">
// SEARCH ENGINES INIT
var arr = new Array();
arr[arr.length] = new Array("Web", "http://www.google.com/search?q=");
arr[arr.length] = new Array("Images", "http://images.google.com/images?q=");
arr[arr.length] = new Array("Knoweledge", "http://en.wikipedia.org/wiki/Special:Search?search=");
arr[arr.length] = new Array("Videos", "http://www.youtube.com/results?search_query=");
arr[arr.length] = new Array("Movies", "http://www.imdb.com/find?q=");
arr[arr.length] = new Array("Torrents", "http://thepiratebay.org/search/");
// SEARCH FORM INIT
function addOptions() {
// Add the options to the select dropdown.
var nOptions = arr.length;
var optionText = '';
for (var i = 0; i < nOptions; i++) {
optionText += '<option value="' + i + '">' + arr[i][0] + '</option>'
}
//alert('optionText = ' + optionText);
// Add the options to the select drop down.
$('select#whichEngine').html(optionText);
// set the second option as default. This can be changed, if required.
$('select#whichEngine option:eq(1)').attr('selected', true);
}
function startSearch() {
var searchEngineIndex = $('select#whichEngine option:selected').attr('value');
searchEngineIndex = parseInt(searchEngineIndex, 10);
var searchString = $('input#searchText').val();
if (searchEngineIndex >= 0 && searchString) {
var searchURL = arr[searchEngineIndex][1] + searchString;
//alert('location = ' + searchURL);
window.location.href = searchURL;
}
return false;
}
function checkKey(e) {
var character = (e.which) ? e.which : event.keyCode;
if (character == '13') {
return startSearch();
}
}
$(function() {
// Add the options to the select drop down.
addOptions();
// Add focus to the search text box.
$('input#searchText').focus();
// Hook the click event handler to the search button.
$('input[type=button]').click(startSearch);
$('input#searchText').keyup(checkKey);
});
</script>
</head>
<body>
<div id="wrapper">
<div id="logo"></div>
<form name="searchForm" method="POST" action="javascript:void(0)">
<input id="searchText" name="searchText" type="text"/>
<span id="color"></span>
<select tabindex="1" id="whichEngine" name="whichEngine"></select>
<br />
<input tabindex="2" type="button"value="Search"/>
</form>
</div>
</body>
</html>
答案 2 :(得分:0)
您在处理<select>
值和选项方面遇到了一些错误。我会像这样重新组织你的JavaScript:
// SEARCH ENGINES
var arr = [["Web", "http://www.google.com/search?q="],
["Images", "http://images.google.com/images?q="],
["Knowledge", "http://en.wikipedia.org/wiki/Special:Search?search="],
["Videos", "http://www.youtube.com/results?search_query="],
["Movies", "http://www.imdb.com/find?q="],
["Torrents", "http://thepiratebay.org/search/"]];
// SEARCH FORM INIT
function addOptions(){
var sel=document.searchForm.whichEngine;
for(var i=0;i<arr.length;i++) {
sel.options[i]=new Option(arr[i][0],arr[i][1]);
}
}
function startSearch(){
var searchString = document.searchForm.searchText.value;
if(searchString!==''){
var mySel = document.searchForm.whichEngine;
var finalLocation = mySel.options[mySel.selectedIndex].value;
finalLocation += encodeURIComponent(searchString);
location.href = finalLocation;
}
return false;
}
function checkKey(e){
var character=(e.which) ? e.which : event.keyCode;
return (character=='13') ? startSearch() : null;
}
我还会将您的onload
处理程序移到JavaScript的主体中:
window.onload = function() {
addOptions();
document.searchForm.searchText.focus();
};
我还对您的HTML进行了一些更改:
<body>
<div id="wrapper">
<div id="logo"></div>
<form name="searchForm" method="POST" action="." onsubmit="return false;">
<input name="searchText" type="text" onkeypress="checkKey(event);" />
<span id="color"></span>
<select tabindex="1" name="whichEngine" selected="Web"></select><br />
<input tabindex="2" type="button" value="Search"
onclick="startSearch();" />
</form>
</div>
</body>
答案 3 :(得分:0)
你可以指定你想在引擎数组中预选的哪个egine:
// SEARCH ENGINES INIT
// I've used array literals for brevity
var arr = [
["Web", "http://www.google.com/search?q="],
["Images", "http://images.google.com/images?q="],
["Knoweledge", "http://en.wikipedia.org/wiki/Special:Search?search="],
/*
* notice that this next line has an extra element which is set to true
* this is my default
*/
["Videos", "http://www.youtube.com/results?search_query=", true],
["Movies", "http://www.imdb.com/find?q="],
["Torrents", "http://thepiratebay.org/search/"]
];
然后在你的设置功能中:
// SEARCH FORM INIT
function addOptions() {
var sel = document.searchForm.whichEngine;
for (var i = 0; i < arr.length; i++) {
// notice the extra third argument to the Option constructor
sel.options[i] = new Option( arr[i][0], i, arr[i][2] );
}
}
答案 4 :(得分:0)
如果您唯一关心的是预先选择引擎负载,请不要“过度设计”它。
var Web = "http://www.google.com/search?q=";
var Images = "http://images.google.com/images?q=";
var Knowledge = "http://en.wikipedia.org/wiki/Special:Search?search=";
var Videos = "http://www.youtube.com/results?search_query=";
var Movies = "http://www.imdb.com/find?q=";
var Torrents = "http://thepiratebay.org/search/";
function addOptions(source){
var sel=document.searchForm.whichEngine;
for(var i=0,l=arr.length;i<l;i++){
sel.options[i]=new Option(arr[i][0], i);
}
}
然后将您在body标签上的参数插入到预定义的变量中。如果你想要一些随机的东西,用你的等式创建一个新函数来选择一个随机变量,然后在你的新函数中加载你的addOptions(函数)。然后从body标签中删除addOptions。
<body onload="addOptions(Web);document.forms.searchForm.searchText.focus()">