js简单继承的实现

function base() {
this.member = "dnnsun_Member";
this.method = function() {
window.alert(this.member);
}
}
function extend(child, b) {
b.call(child);
}
var child={
test:function(){
window.alert("in child");
window.alert(child.member);
}
};
extend(child, base);
window.alert(child.member);
window.alert(child.method);
child.test()