JavaScript 验证是否输入
<!DOCTYPE html>
<html>
<head>
<title>2.2节,验证是否输入</title>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
</head>
<body>
<h2>验证是否输入</h2>
<input type='text' id='strs' value=' 需要过滤空格 '>
<input type='button' id='isContent' value='验证是否为空'><br>
<script type="text/javascript">
window.onload = function(){
var _isContent = document.getElementById("isContent"),
_strs = document.getElementById("strs");
_isContent.onclick = function(){
if(!_strs.value.replace( /^(\s|\u00A0)+|(\s|\u00A0)+$/g, "" )){
alert("您的输入为空！");
}else{
alert("您的输入不为空！");
}
}
};
</script>
</body>
</html>