/* Set selected index of select */
function set_select_option(field, value){
   if(field==null) return;
   if(field.options==null) return;
   var len = field.options.length ;
   for(i = 0;i< len ;i++){
      if( field.options(i).value == value )
       field.options(i).selected = true;
  }
}


/* Check all checkboxes  */
function checkall(  form, state) {
	if(form==null){
		alert('checkall:form parameter is null');
		return;
	}
	var t_elements = form.elements;
	for (var i = 0; i < t_elements.length; i++) {
    	if(t_elements[i].type == 'checkbox') {
      		t_elements[i].checked = state;
   		}
  	}
}


function confirm_action( msg, form, action){
   var c;
   c = confirm(msg);
   if(c){
     if(form._action  != null)
   	form._action.value = action;
     else{
	alert('"_action" field not defined in form, or form name error');
	}
   }
   return c;
}


function set_form_message(form, message, icon){
	var msg_span = document.all(form.name+'_MESSAGE');
	if(message==null){
		msg_span.style.display = 'none';
	}else{
		if(icon!=null)
		message = '<img src="'+icon+'">' + message;
		msg_span.innerHTML = message ;
		msg_span.style.display = 'inline';
	}
}

function set_form_warning(form, message){
	set_form_message(form,message,'warning.gif');
}

function clear_form_message(form){
	var msg_span = document.all(form.name+'_MESSAGE');
	msg_span.style.display = 'none';
}

function get_sum_value( _form, _field_prefix){
	var elms = _form.elements;
	var rt = 0;
	for(i = 0;i < elms.length;i++){
	   if (elms[i].name.indexOf(_field_prefix) >= 0 
	       //&& elms[i].type == 'text' //Ŀǰˇedit
	   )
	   	if ('' != elms[i].value)
	   		rt += parseFloat(elms[i].value);
	}
	return Math.round(rt * 100)/100;
}

<!-- 输入串是否全是数字 -->
function checkInteger(str)
{
   	var reg = /^\d+$/;
   	if(arr=str.match(reg)){
      		return true;
   	}else{
     		alert("必须输入一个整数");
      		return false;
   	}
}
function checkInteger2(str){
    var reg = /^\d+$/;
    if(str==""){return true;}
    if(arr=str.match(reg)){
    	return true;
   }else{
   	alert("请输入整数");
   	return false;
   }
}
<!-- 输入串是否是浮点型数字 -->
function checkFloat(str)
{
   	var reg = /^-?\d*(\.)?\d+$/;
    	if(arr=str.match(reg)){
      		return true;
   	}else{
     		alert("必须输入一个数字");
      		return false;
   	}
}
function checkFloat2(str){
   	var reg = /^-?\d*(\.)?\d+$/;
        if(str==""){
      		return true;
        }
   	if(arr=str.match(reg)){
      		return true;
   	}else{
     		alert("请输入数字");
      		return false;
   	}
}	

function checkCertificate(str){
  	var reg = /^((\d{15})|((\d){17}(\d|X){1}))$/;
   	if(arr=str.match(reg)){
      		return true;
   	}else{
     		alert("身份证位数或格式不对");
      		return false;
   	}
}	

/*
function set_field_message(_field, message){
   if(_field==null){
		alert("[set_field_message] field parameter is null");
		return;
	}
   var msg_span = _field.name +'_span';
   var span = document.all(msg_span);
   if(span == null){
		alert("[set_field_message] can't find span object that contains "+_field.name );
		return;
	}

   span	
}
*/