//除去字符串的空格
String.prototype.trim = function()
{
    return this.replace(/(^\s*)|(\s*$)/g, "");
}
//回车提交
function clickButton(e, buttonid){ 
      var bt = document.getElementById(buttonid); 
      if (typeof bt == 'object'){ 
            if(navigator.appName.indexOf("Netscape")>(-1)){ 
                  if (e.keyCode == 13){ 
                       var fevent = document.createEvent("MouseEvents");  
                       fevent .initEvent("click",true,true);  
                       bt.dispatchEvent(fevent); 
                    //    bt.click(); 
                        return false; 
                  } 
            } 
            if (navigator.appName.indexOf("Microsoft Internet Explorer")>(-1)){ 
                  if (event.keyCode == 13){ 
                        bt.click(); 
                        return false; 
                  } 
            } 
      } 
} 

//长度
function checkByteLength(str,minlen,maxlen,isbyte) {
	if (str == null) return false;
	var l = str.length;
	var blen = 0;
	for(i=0; i<l; i++) {
	        if(isbyte){
		       if ((str.charCodeAt(i) & 0xff00) != 0) {
			       blen ++;
			    } 
		     }
		blen ++;
	}
	if (blen > maxlen || blen < minlen) {
		return false;
	}
	return true;
}

//列表菜单
function site_select_listmenu(obj)
{
  obj=document.getElementById(obj);
  if(obj!=null){
   obj.className='on'
  }
}

//focus
function site_input_focus(obj,name)
{
    obj.className+=" "+name;
}

//blur
function site_input_blur(obj,name)
{
    obj.className=obj.className.replace(new RegExp(" "+name+"\\b"), "");
}


function headerpost_submit(input,btn)
{
    var comment=document.getElementById(input);
    if(comment.value.trim()=="" || comment.value.trim()=="Share something...")
    {
        alert("Please enter your message.");
        comment.value="";
        comment.focus();
        return false;
    }
   
   return true; 
}