|
用JS显示文字的例子:
<html> <body>
<script type="text/javascript"> document.write("Hello World!") </script>
</body> </html>
用HTML标签来格式化文本的例子:
<html> <body>
<script type="text/javascript"> document.write("<h1>Hello World!</h1>") </script>
</body> </html>
书写JS位置的例子:
打开页面弹出窗口的例子
<html> <head> <script type="text/javascript"> function message() { alert("网页教学网欢迎你的光临") } </script> </head>
<body onload="message()">
</body> </html>
在BODY区内输出显示文本的例子:
<html> <head> </head>
<body>
<script type="text/javascript"> document.write("欢迎光临网页教学网http://www.webjx.com") </script>
</body> </html>
调用其它的一个JS文件的例子:
<html> <head> </head> <body>
<script src="xxx.js"> </script>
<p> The actual script is in an external script file called "xxx.js". </p>
</body> </html>
变量的使用
变量使用的例子:
<html> <body>
<script type="text/javascript"> var name = "Hege" document.write(name) document.write("<h1>"+name+"</h1>") </script>
<p>This example declares a variable, assigns a value to it, and then displays the variable.</p>
<p>Then the variable is displayed one more time, only this time as a heading.</p>
</body> </html>
函数的例子
函数使用的一个例子:
<html> <head>
<script type="text/javascript"> function myfunction() { alert("HELLO") } </script>
</head> <body>
<form> <input type="button" onclick="myfunction()" value="Call function"> </form>
<p>By pressing the button, a function will be called. The function will alert a message.</p>
</body> </html>
带一个参数的函数的例子:
<html> <head>
<script type="text/javascript"> function myfunction(txt) { alert(txt) } </script>
</head> <body>
<form> <input type="button" onclick="myfunction('Hello')" value="Call function"> </form>
<p>By pressing the button, a function with an argument will be called. The function will alert this argument.</p>
</body> </html>
不同的两个参数调用函数的例子:
<html> <head> <script type="text/javascript"> function myfunction(txt) { alert(txt) } </script> </head>
<body> <form> <input type="button" onclick="myfunction('Good Morning!')" value="In the Morning">
<input type="button" onclick="myfunction('Good Evening!')" value="In the Evening"> </form>
<p> When you click on one of the buttons, a function will be called. The function will alert the argument that is passed to it. </p>
</body> </html>
利用函数返回值的例子:
<html> <head>
<script type="text/javascript"> function myFunction() { return ("Hello, have a nice day!") } </script>
</head> <body>
<script type="text/javascript"> document.write(myFunction()) </script>
<p>The script in the body section calls a function.</p>
<p>The function returns a text.</p>
</body> </html>
带参数的函数返回值的例子:
<html> <head>
<script type="text/javascript"> function total(numberA,numberB) { return numberA + numberB } </script>
</head> <body>
<script type="text/javascript"> document.write(total(2,3)) </script>
<p>The script in the body section calls a function with two arguments, 2 and 3.</p>
<p>The function returns the sum of these two arguments.</p>
</body> </html>
条件语句的例子
简单条件语句的例子:
<html> <body>
<script type="text/javascript"> var d = new Date() var time = d.getHours()
if (time < 10) { document.write("<b>Good morning</b>") } </script>
<p> This example demonstrates the If statement. </p>
<p> If the time on your browser is less than 10, you will get a "Good morning" greeting. </p>
</body> </html>
if ... else 的条件语句的例子:
<html> <body>
<script type="text/javascript"> var d = new Date() var time = d.getHours()
if (time < 10) { document.write("<b>Good morning</b>") } else { document.write("<b>Good day</b>") } </script>
<p> This example demonstrates the If...Else statement. </p>
<p> If the time on your browser is less than 10, you will get a "Good morning" greeting. Otherwise you will get a "Good day" greeting. </p>
</body> </html>
用随机数产生连接的例子:
<html> <body>
<script type="text/javascript"> var r=Math.random() if (r>0.5) { document.write("<a href='http://www.w3schools.com'>Learn Web Development!</a>") } else { document.write("<a href='http://www.refsnesdata.no'>Visit Refsnes Data!</a>") } </script>
</body> </html>
多条件的语句实现的例子:
<html> <body> <script type="text/javascript"> var d = new Date() theDay=d.getDay() switch (theDay) { case 5: document.write("Finally Friday") break case 6: document.write("Super Saturday") break case 0: document.write("Sleepy Sunday") break default: document.write("I'm really looking forward to this weekend!") } </script>
<p>This example demonstrates the switch statement.</p>
<p>You will receive a different greeting based on what day it is.</p>
<p>Note that Sunday=0, Monday=1, Tuesday=2, etc.</p>
</body> </html>
循环的例子:
for循环的一个例子:
<html> <body>
<script type="text/javascript"> for (i = 0; i <= 5; i++) { document.write("The number is " + i) document.write("<br>") } </script>
<p>Explanation:</p>
<p>The for loop sets <b>i</b> equal to 0.</p>
<p>As long as <b>i</b> is less than , or equal to, 5, the loop will continue to run.</p>
<p><b>i</b> will increase by 1 each time the loop runs.</p>
</body> </html>
复杂循环的一个例子:
<html> <body>
<script type="text/javascript"> for (i = 1; i <= 6; i++) { document.write("<h" + i + ">This is header " + i) document.write("</h" + i + ">") } </script>
</body> </html>
按条件循环while的例子:
<html> <body>
<script type="text/javascript"> i = 0 while (i <= 5) { document.write("The number is " + i) document.write("<br>") i++ } </script>
<p>Explanation:</p>
<p><b>i</b> equal to 0.</p>
<p>While <b>i</b> is less than , or equal to, 5, the loop will continue to run.</p>
<p><b>i</b> will increase by 1 each time the loop runs.</p>
</body> </html>
do...while循环的例子:
<html> <body>
<script type="text/javascript"> i = 0 do { document.write("The number is " + i) document.write("<br>") i++ } while (i <= 5) </script>
<p>Explanation:</p>
<p><b>i</b> equal to 0.</p>
<p>The loop will run</p>
<p><b>i</b> will increase by 1 each time the loop runs.</p>
<p>While <b>i</b> is less than , or equal to, 5, the loop will continue to run.</p>
</body> </html>
字符串对象的例子:
检测字符串长度的例子:
<html> <body>
<script type="text/javascript"> var str="W3Schools is great!" document.write("<p>" + str + "</p>") document.write(str.length) </script>
</body> </html>
检测子字符串位置的例子:
<html> <body>
<script type="text/javascript"> var str="W3Schools is great!" var pos=str.indexOf("School") if (pos>=0) { document.write("School found at position: ") document.write(pos + "<br />") } else { document.write("School not found!") } </script>
<p>This example tests if [1] [2] [3] [4] [5] [6] [7] 下一页 [网页制作]Ultradev实例教程:5 做一个相对简单的网站后台(3) [网页制作]Ultradev实例教程:5 做一个相对简单的网站后台(2) [网页制作]Ultradev实例教程:5 做一个相对简单的网站后台(1) [网页制作]Ultradev实例教程:4 插件的安装与使用 [网页制作]Ultradev实例教程:3.7 创建一个简单的查询 [网页制作]Ultradev实例教程:3.6 删除纪录 [网页制作]Ultradev实例教程:3.5 编辑数据库中的纪录 [网页制作]Ultradev实例教程:3.4 向数据库添加纪录 [网页制作]Ultradev实例教程:3.3 应用数据库创建动态网页 [网页制作]Ultradev实例教程:3.2 创建数据库连接
|