js原生代码实现数据双向绑定

<!--使用方法-->
<div data-bind-1="name"></div>
<input type="text" data-bind-1="name" />
<script>
$.DBind(1).set("name", "123");
</script>

(function() {
//封装成jqery插件
jQuery.DBind = function(id) {
return new DBind(id);
};
//下面是具体的实现
function DataBinder(object_id) {
// Create a simple PubSub object
var pubSub = {
callbacks: {},

on: function(msg, callback) {
this.callbacks[msg] = this.callbacks[msg] || [];
this.callbacks[msg].push(callback);
},

publish: function(msg) {
this.callbacks[msg] = this.callbacks[msg] || [];
for(var i = 0, len = this.callbacks[msg].length; i < len; i++) {
this.callbacks[msg][i].apply(this, arguments);
}
}
},

data_attr = "data-bind-" + object_id,
message = object_id + ":input",
timeIn;

changeHandler = function(evt) {
var target = evt.target || evt.srcElement, // IE8 compatibility
prop_name = target.getAttribute(data_attr);

if(prop_name && prop_name !== "") {
clearTimeout(timeIn);
timeIn = setTimeout(function() {
pubSub.publish(message, prop_name, target.value);
}, 50);

}
};

// Listen to change events and proxy to PubSub
if(document.addEventListener) {
document.addEventListener("input", changeHandler, false);
} else {
// IE8 uses attachEvent instead of addEventListener
document.attachEvent("oninput", changeHandler);
}

// PubSub propagates changes to all bound elements
pubSub.on(message, function(evt, prop_name, new_val) {
var elements = document.querySelectorAll("[" + data_attr + "=" + prop_name + "]"),
tag_name;

for(var i = 0, len = elements.length; i < len; i++) {
tag_name = elements[i].tagName.toLowerCase();

if(tag_name === "input" || tag_name === "textarea" || tag_name === "select") {
elements[i].value = new_val;
} else {
elements[i].innerHTML = new_val;
}
}
});

return pubSub;
}

function DBind(uid) {
var binder = new DataBinder(uid),

user = {
// ...
attributes: {},
set: function(attr_name, val) {
this.attributes[attr_name] = val;
// Use the `publish` method
binder.publish(uid + ":input", attr_name, val, this);
},
get: function(attr_name) {
return this.attributes[attr_name];
},

_binder: binder
};

// Subscribe to the PubSub
binder.on(uid + ":input", function(evt, attr_name, new_val, initiator) {
if(initiator !== user) {
user.set(attr_name, new_val);
}
});

return user;
}
})();