您可以使用JavaScript创建客户端图像映射.客户端图像映射由< img/> 标记的usemap属性启用,并由特殊< map>定义.和< area> 扩展标记.
使用< img/>将要形成地图的图像插入到页面中元素正常,但它带有一个名为usemap的额外属性. usemap 属性的值是< map>上的name属性的值.您将要遇到的元素,前面有一个井号或一个井号.
< map> element实际上为图像创建了地图,通常在< img/>之后直接跟随.元件.它充当< area/>的容器.实际定义可点击热点的元素. < map> element只携带一个属性,即name属性,它是标识地图的名称.这是怎么< img/> element知道哪个< map>要使用的元素.
< area> element指定定义每个可点击热点边界的形状和坐标.
以下代码将图像映射和JavaScript组合在一起,当鼠标移动到不同的部分时,在文本框中生成一条消息图片.
<html> <head> <title>Using JavaScript Image Map</title> <script type="text/javascript"> <!-- function showTutorial(name) { document.myform.stage.value = name } // --> </script> </head> <body> <form name = "myform"> <input type = "text" name = "stage" size = "20" /> </form> <!-- Create Mappings --> <img src = "//images/usemap.gif" alt = "HTML Map" border = "0" usemap = "#tutorials"/> <map name = "tutorials"> <area shape = "poly" coords = "74,0,113,29,98,72,52,72,38,27" href = "/perl/index.htm" alt = "Perl Tutorial" target = "_self" onMouseOver = "showTutorial('perl')" onMouseOut = "showTutorial('')"/> <area shape = "rect" coords = "22,83,126,125" href = "/html/index.htm" alt = "HTML Tutorial" target = "_self" onMouseOver = "showTutorial('html')" onMouseOut = "showTutorial('')"/> <area shape = "circle" coords = "73,168,32" href = "/php/index.htm" alt = "PHP Tutorial" target = "_self" onMouseOver = "showTutorial('php')" onMouseOut = "showTutorial('')"/> </map> </body> </html>
成功执行上述代码后会显示以下输出.您可以通过将鼠标光标放在图像对象上来感受地图概念.