web1

 1 <!DOCTYPE html>
 2 <html>
 3 <head>
 4     <title>web0923</title>
 5     <script>
 6         function displayDate() {
 7             document.getElementById("date").innerHTML = Date();
 8         }
 9         function changePic() {
10             alert("Ah?");
11             element = document.getElementById('myImg');
12             element.style.color = "#ff0000";
13             element.height = "300";
14             element.width = "300";
15             if (element.src.match("gr+")) {
16                 element.src = "LockScreen.jpg";
17             }
18             else {
19                 element.src = "grass.jpg";
20             }
21         }
22     </script>
23 </head>
24 <body>
25     <h1>Title</h1>
26     <p>Para</p>
27     <div id="abc">
28         <p id="date"></p>
29         <button type="button" onclick="displayDate()">display date</button>
30     </div>
31     <div id="image">
32         <img id="myImg" src="grass.jpg" width="100" height="100">
33         <button type="button" onclick="changePic()">change picture</button>
34     </div>
35     <div>
36         <input id="AccountID" type="text">
37         <script>
38             function judgeNumber() {
39                 var str = document.getElementById("AccountID").value;
40                 if (str == "" || isNaN(str)) {
41                     alert("This is not a number");
42                 }
43             }
44         </script>
45         <button type="button" onclick="judgeNumber()">Submit</button>
46     </div>
47 </body>
48 </html>
View Code
学了很基础的一部分，getElementById("**控件名字**").value,一开始忘记加引号，导致怎么都出不来。。。