//Add more fields dynamically.
function addField(area,field,limit,coluna) {
	if(!document.getElementById) return; //Prevent older browsers from getting any further.
		var field_area = document.getElementById(area);
		var all_inputs = field_area.getElementsByTagName("input"); //Get all the input fields in the given area.
		//Find the count of the last element of the list. It will be in the format '<field><number>'. If the
		// field given in the argument is 'friend_' the last id will be 'friend_4'.
		var last_item = all_inputs.length - 1;
		var last = all_inputs[last_item].id;
		var pos1 = last.indexOf("[")+1;
		var pos2 = last.indexOf("]");
		var count = Number(last.substr(pos1,(pos2-pos1)))+1;
	//If the maximum number of elements have been reached, exit the function.
	// If the given limit is lower than 0, infinite number of fields can be created.
	if(count > limit && limit > 0) return;
	//Add more fields dynamically.
	
	if(document.createElement) { //W3C Dom method.rand
		var rand = (Math.round((Math.random()*200)+1));
		var foo = new Date;
		var time = foo.getTime();
		var li = document.createElement("li");
		var input = document.createElement("input");
		var nomeid = field+'[novos]['+(time+rand)+']['+coluna+']'
		
		input.id = nomeid;
		input.name = nomeid;
		input.type = "text"; //Type of field - can be any valid input type like text,file,checkbox etc.
		li.appendChild(input);
		field_area.appendChild(li);
	} else { //Older Method
		field_area.innerHTML += "<li><input name='"+nomeid+"' id='"+nomeid+"' type='text' /></li>";
	}
}

function clear(campo){
	document.informe.campo.value = '';
}

<!--//
function display(id) {
	if (document.getElementById) {
		document.getElementById(id).style.display = "";
	}else if (document.layers) {
		document.layers[id].visibility = "show";
	}else if (document.all) {
		document.all[id].style.visibility = "visible";
	}else {
		//alert('Unknown browser category.');
	}
	return true;
}

function hide(id) {
	if (document.getElementById) {
		document.getElementById(id).style.display = "none";
	}else if (document.layers) {
		document.layers[id].visibility = "hide";
	}else if (document.all) {
		document.all[id].style.visibility = "hidden";
	}else {
		//alert('Unknown browser category.');
	}
	return true;
}

function inputSwitch(IDvalid, arrayIDremove){
	if(document.getElementById(IDvalid).value.length > 0){
		for (i in arrayIDremove) { 
			if(document.getElementById(arrayIDremove[i]) != null ){
				hide(arrayIDremove[i]);
			}
		};
	}else{
		for (i in arrayIDremove) { 
			if(document.getElementById(arrayIDremove[i]) != null ){
				display(arrayIDremove[i]);
			}
		};
	}
}
//-->