本文实例讲解了javascript输入框自动下拉补全操作，仿百度、谷歌搜索框提示，具体内容如下
效果图：
具体代码：
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<HTML>
<HEAD>
<TITLE> New Document </TITLE>
<META NAME="Generator" CONTENT="EditPlus">
<META NAME="Author" CONTENT="">
<META NAME="Keywords" CONTENT="">
<META NAME="Description" CONTENT="">
<script type="text/javascript" src="jquery.js"></script>
<script type="text/javascript">
/*自动下拉补全 zhk */
var highlightindex=-1;//当前高亮的节点
$(document).ready(function(){
var wordInput=$("#word");
var wordInputOffset=wordInput.offset();
$("#auto").hide().css("border","1px black solid").css("position","absolute")
.css("top",wordInputOffset.top+wordInput.height()+5+"px")
.css("left",wordInputOffset.left+"px").width(wordInput.width()+2);
wordInput.keyup(function (event){
var myEvent=event||window.event;
var keyCode=myEvent.keyCode;
if(keyCode>=65&&keyCode<=90||keyCode==8||keyCode==46){
var wordText=$("#word").val();
var autoNode=$("#auto");
if(wordText!=""){
var wordNodes=$("span");
autoNode.html("");
wordNodes.each(function(i){
var wordNode=$(this);
var newDivNode=$("<div>").attr("id",i);
newDivNode.html(wordNode.text()).appendTo(autoNode);
newDivNode.mouseover(function(){//鼠标进入
if(highlightindex!=-1){
$("#auto").children("div").eq(highlightindex)
.css("background-color","white");
}
highlightindex=$(this).attr("id");
$(this).css("background-color","red");
})
newDivNode.mouseout(function(){//鼠标移除
$(this).css("background-color","white");
})
newDivNode.click(function(){//点击
var comText=$(this).text();
$("#auto").hide();
highlightindex=-1;
$("#word").val(comText);
})
})
if(wordNodes.length>0){
autoNode.show();
}else{
autoNode.hide();
highlightindex=-1;
}
}else{
autoNode.hide();
highlightindex=-1;
}
}else if(keyCode==38||keyCode==40){
if(keyCode==38){//向上
var autoNodes=$("#auto").children("div");
if(highlightindex!=-1){
autoNodes.eq(highlightindex).css("background-color","white");
highlightindex--;
}else{
highlightindex=autoNodes.length-1;
}
if(highlightindex==-1){
highlightindex=autoNodes.length-1;
}
autoNodes.eq(highlightindex).css("background-color","red");
}
if(keyCode==40){
var autoNodes=$("#auto").children("div");
if(highlightindex!=-1){
autoNodes.eq(highlightindex).css("background-color","white");
}
highlightindex++;
if(highlightindex==autoNodes.length){
highlightindex=0;
}
autoNodes.eq(highlightindex).css("background-color","red");
}
}else if(keyCode==13){
if(highlightindex!=-1){
var comText=$("#auto").hide().children("div").eq(highlightindex).text();
highlightindex=-1;
$("#word").val(comText);
}else{
alert("文本框中的【"+$("#word").val()+"】被提交了");
$("#auto").hide();
$("#word").get(0).blur();//失去焦点
}
}
});
$("input [type='button']").click(function(){
alert("文本框中的【"+$("#word").val()+"】被提交了");
});
})
</script>
</HEAD>
<BODY>
<input type="text" id="word">
<input type="button" value="提交">
<div id="auto"></div>
<p>
<span>aaa</span>
<span>abc</span>
<span>abd</span>
<span>bbc</span>
<span>beb</span>
<span>cer</span>
<span>erd</span>
<span>beg</span>
<p>
</BODY>
</HTML>
以上就是本文的全部内容，希望对大家学习javascript程序设计有所帮助。