Заполнение input из кнопки

function addTextToInput(anElement) { 
  var text = document.getElementById('jaloby').value; 
  if (text != "") 
    text += ","; 
  text += anElement.innerText; 
  document.getElementById('jaloby').value = text; 
}

<input id="jaloby" /> 
<br/> 
<button type="button" onclick="addTextToInput(this)">1</button> 
<button type="button" onclick="addTextToInput(this)">2</button> 
<button type="button" onclick="addTextToInput(this)">3</button>

<li> 
  <a href="#" onClick="document.getElementById('jaloby').value = 'Кариес'">1</a> 
</li> 
 
<input id="jaloby"/>

<li> 
  <a href="" onClick="document.getElementById('jaloby').value = 'Кариес'; return false">1</a> 
</li> 
 
<input id="jaloby"/>

<li> 
  <a href="javascript:void(document.getElementById('jaloby').value = 'Кариес')">1</a> 
</li> 
 
<input id="jaloby"/>

<li> 
  <a href="javascript:(function(){document.getElementById('jaloby').value = 'Кариес'})()">1</a> 
</li> 
 
<input id="jaloby" />

;(function ($window) { 
   'use strict'; 
 
    var textTemplate = 'Выбран зуб №$1, диагноз $2;\n'; 
 
    var insertAfter = function (elem, refElem) { 
    	var parent = refElem.parentNode; 
    	var next = refElem.nextSibling; 
    	if (next) { 
    		return parent.insertBefore(elem, next); 
    	} else { 
    		return parent.appendChild(elem); 
    	} 
    }; 
 
    var brand = $window.brand = { 
       init: function (parentElement, toothCount, diagnoseList) { 
    		var self = this; 
 
    		var container = $window.document.createElement('div'); 
    		container.classList.add('container'); 
 
    		var input = $window.document.createElement('textarea'); 
    		input.classList.add('input'); 
 
    		container.appendChild(input); 
    		insertAfter(container, parentElement); 
 
    		for (var i = 1; i <= toothCount; i++) { 
    			var button = $window.document.createElement('button'); 
    			button.setAttribute('data-number', i); 
    			button.classList.add('btn-number'); 
    			button.innerText = i; 
    			button.addEventListener('click', function () { 
    			   self.textTemplate = textTemplate.replace('$1', this.dataset.number); 
    			}); 
    			container.appendChild(button); 
    		} 
    		for (var i = 0; i < diagnoseList.length; i++) { 
    			var button = $window.document.createElement('button'); 
    			button.setAttribute('data-diagnose', diagnoseList[i]); 
    			button.classList.add('btn-diagnose'); 
    			button.innerText = diagnoseList[i]; 
    			button.addEventListener('click', function () { 
    			   if (self.textTemplate) { 
    				 input.value += self.textTemplate.replace('$2', this.dataset.diagnose); 
    				 self.textTemplate = ''; 
    			   } 
    			}); 
    			container.appendChild(button); 
    		} 
    	}, 
    	textTemplate: '', 
    	defaultDiagnoseList: ['Альвеолы', 'Галитоз', 'Кариес'] 
    } 
})(window); 
 
brand.init(window.document.body, 32, brand.defaultDiagnoseList);

.container { 
	margin: 20px auto; 
	width: 450px; 
} 
.container .input { 
	width: 100%; 
	resize: vertical; 
	min-height: 100px; 
	border-radius: 4px; 
} 
.container .btn-number { 
	background-color: #fff; 
	color: #929292; 
	border: 1px solid #aaa; 
	border-radius: 4px; 
	padding: 4px; 
	margin: 2px; 
	outline: none; 
} 
.container .btn-diagnose { 
	background-color: #fdd; 
	color: #555; 
	border: 1px solid #aaa; 
	border-radius: 4px; 
	padding: 4px; 
	margin: 2px; 
	outline: none; 
}