基本的原理是在当前窗口创建了一个iframe，然后将相关关键词的提示列表在iframe中，并通过列表点选将选定项放到搜索框中。
能这么快的能将所有相关关键词的检索数列出，看来所有的提示词已经提前进行了预搜索和数量记录。试了一下"sex"，没有相关检索提示，看来对搜索词进行了严格的色情过滤。
另外：这一动态列表功能也应用在GMail的地址栏自动输入完成中，如图：
Google自动完成的源代码如下：// Copyright 2004 and onwards Google Inc. var w=""; var pa=false; var ta=""; var da=false; var g=""; var G=""; var m=""; var j=-1; var h=null; var Z=-1; var za=null; var Ca=5; var q=""; var Lb="div"; var Bb="span"; var la=null; var a=null; var b=null; var Xa=null; var mb=null; var X=null; var ha=null; var ra=false; var kc=null; var hc=null; var Ua=new Object(); var ca=1; var Aa=1; var Y=false; var na=-1; var Va=(new Date()).getTime(); var Q=false; var k=null; var sa=null; var E=null; var B=null; var aa=null; var Ba=false; var Ka=false; var p=60; var ia=null; var ya=null; var W=0; InstallAC=function(frm,fld,sb,pn,rl,hd,sm,ufn){ la=frm; a=fld; Xa=sb; if(!pn)pn="search"; ia=pn; var Kb="en|"; var Jb="zh-CN|zh-TW|ja|ko|vi|"; if(!rl||Kb.indexOf(rl+"|")==-1)rl="en"; ha=nb(rl); if(Jb.indexOf(ha+"|")==-1){ X=true; Y=false; Ba=false} else{ X=false; if(ha.indexOf("zh")==0)Y=false; else Y=true; Ba=true} if(!hd)hd=false; ya=hd; if(!sm)sm="query"; w=sm; mb=ufn; ac()} ; function Yb(){ ra=true; 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k.send(null)} } function S(Wa){ a.value=Wa; aa=Wa} 源代码写的非常“拥挤”，我不得不用以下代码做了beautifier: perl -pe 's/;/;\n/g' ac.js |perl -pe 's/}/}\n/g'|perl -pe 's/{/{\n/g' > ac.js.txt 附： 你尝试过把26个英文字母从A~Z输入，那么，排第一的将会是哪些单词呢： a---amazon b---best buy c---cnn d---dictionary e---ebay f---firefox g---games h---hotmail i---ikea j---jokes k---kazaa l---lyrics m---mapquest n---news o---online dictionary p---paris hilton q---quotes r---recipes s---spybot t---tara reid u---ups v---verizon w---weather x---xbox y---yahoo z---zip codes
车东[1]和huttmean[2]都说了google搜索建议的好处。
[1]
[2]
车东说得更好。还给了代码。不愧技术派。
我不在乎这个功能。：）gmail中还是很好
用的，因为不用自己记忆email地址了。就
像使用本地email程序一样。google中用处
不大。
我写这些是想问个问题。我不是技术派我
是较真儿派。：）
google中不但有提示还有记忆搜索过的条
目（或这是浏览器在记忆？）