​x
 
<!DOCTYPE html>
<html>
<head>
<script src="http://libs.baidu.com/jquery/1.10.2/jquery.min.js">
</script>
<script>
$(document).ready(function(){
  $("button").click(function(){
    alert($("input:text").val());
  });
});
</script>
</head>
<body>
​
Firstname: <input type="text" name="fname" value="Peter"><br>
Lastname: <input type="text" name="lname" value="Griffin"><br><br>
<button>Return the value of the first input field</button>
​
</body>
</html>