代码示例：（标识：hdom_area_target）
<!DOCTYPE html>
<html>
<body>
<img src ="/static/demo/images/eg_planets.jpg"
alt="Planets"
usemap ="#planetmap" />
<map name ="planetmap">
<area shape ="circle" coords ="180,139,14"
href ="/static/demo/html/venus.html" id="venus"
target="_self"/>
</map>
<p>单击按钮可返回图像映射中“venus”区域的 target 属性值。</p>
<button onclick="myFunction()">试一试</button>
<p id="demo"></p>
<script>
function myFunction() {
var x = document.getElementById("venus").target;
document.getElementById("demo").innerHTML = x;
}
</script>
</body>
</html>
