兼容IE和FirFox--禁止输入空字符-定位光标
<script type="text/javascript">var len;//去掉左边空格function ltrim(s) { return s.replace(/(^\s*)/g, ''); } //去掉右边空格function rtrim(s) { return s.replace(/(\s*$)/g, ''); } //去掉左右空格function trim(s){ return rtrim(ltrim(s)); } function clearNoStr(obj){ var start=obj.selectionStart; var end=obj.selectionEnd; var report=document.getElementById(obj.id).value; var reportItem=trim(report); var res=report.substring(start-1,start);if(typeof document.selection != "undefined") {var s=document.selection.createRange(); s.setEndPoint("StartToStart",obj.createTextRange()) len=trim(s.text).length; }else{ obj.focus(); obj.setSelectionRange(start,end); } if(reportItem=='' || reportItem==null){ document.getElementById(obj.id).value=report.substring(report.length); }else{ var count=report.substring(0,report.length-reportItem.length); var countLength=count.length; var countStr=""; //去掉左边的空格符 for(var i=0;i<countLength;i++){ countStr+=" "; } var temp=report.substring(0,1); if(count==countStr){ document.getElementById(obj.id).value=report.substring(countLength); if(temp==" "){ if(typeof document.selection != "undefined") { var range=obj.createTextRange(); range.moveStart('character',0); range.collapse(true); range.select(); }else{ obj.focus(); obj.setSelectionRange(0,0); } } }else{ document.getElementById(obj.id).value=report.substring(0,reportItem.length); } } clearInnerStr(obj,temp,res,start,end);} function clearInnerStr(obj,temp,res,start,end){ var reqStr=document.getElementById(obj.id).value;var size=reqStr.length;var noStr="";var k=0;for(var i=0;i<size;i++){ noStr=reqStr.charAt(i); if(noStr==" "){ k++; IgnoreSpaces(obj.id,reqStr);}}if(typeof document.selection != "undefined") { var range = obj.createTextRange(); range.moveStart('character',len); range.collapse(true); range.select(); }else{if(temp==" "){ obj.setSelectionRange(0,0);}else{ var resStr=document.getElementById(obj.id).value; var resSize=resStr.length; if(res==" "&&k>0){ obj.setSelectionRange(start-k,end-k); }} } }function IgnoreSpaces(id,Str){ var ResultStr = ""; Temp=Str.split(" ");//双引号之间是一个空格 for(i = 0; i < Temp.length; i++){ ResultStr +=Temp[i]; } document.getElementById(id).value=ResultStr;}</script>禁止在内容中输入空字符：<input type="text" id="name" value="" onkeyup="clearNoStr(this);"><p>