function checkform(){var form1=document.myform;try{if(GetContentLength()==0){alert("留言内容不能为空!");return false}}catch(e){if(form1.content.value==""){alert("留言内容不能为空!");form1.content.focus();return false}}try{if(form1.user.value==""){alert("您的姓名不能为空！");form1.user.focus();return false}}catch(e){}try{if(form1.codestr.value==""){alert("请输入验证码！");form1.codestr.focus();return false}}catch(e){}}