<!doctype html>
<html>
<head>
<meta charset="utf-8">
<title>JS基础——if else语句和innerHTML的使用</title>
<style>
#div1{ width:260px; height:200px; border:1px solid #ccc; background:#f4f4f4;}
</style>
<script>
window.onload = function(){
var oDiv = document.getElementById('div1');
var oStrong = document.getElementById('strong1');
var oText = document.getElementById('text1');
var oBtn = document.getElementById('btn1');
oBtn.onclick = function(){
if(oText.value == ''){
alert('亲,说点什么吧~~');
}else{
oDiv.innerHTML = oStrong.innerHTML + oText.value +'<br/>' + oDiv.innerHTML;
oText.value = '';
}
};
};
</script>
</head>
<body>
<div id="div1"></div>
<strong id="strong1">张三:</strong>
<input id="text1" type="text" />
<input id="btn1" type="button" value="提交" />
</body>
</html>