},
set: function (newVal) {
console.log(`更新${newVal}`);
if (value !== newVal) {
value = newVal;
binding._directives.forEach(function (item) {
item.update();
})
}
}
})
}
}
}
myVue.prototype._complie = function (root) {
var _this = this;
var nodes = root.children;
for (var i = 0; i < nodes.length; i++) {
var node = nodes[i];
if (node.children.length) {
this._complie(node);
}
if (node.hasAttribute('v-click')) {
node.onclick = (function () {
var attrVal = nodes[i].getAttribute('v-click');
return _this.$methods[attrVal].bind(_this.$data);
})();
}
if (node.hasAttribute('v-model') && (node.tagName == 'INPUT' || node.tagName == 'TEXTAREA')) {
node.addEventListener('input', (function(key) {
var attrVal = node.getAttribute('v-model');
_this._binding[attrVal]._directives.push(new Watcher(
'input',
node,
_this,
attrVal,
'value'
))
return function() {
_this.$data[attrVal] = nodes[key].value;
}
})(i));
}
if (node.hasAttribute('v-bind')) {
var attrVal = node.getAttribute('v-bind');
_this._binding[attrVal]._directives.push(new Watcher(
'text',
node,
_this,
attrVal,
'innerHTML'
))
}
}
}
function Watcher(name, el, vm, exp, attr) {
this.name = name; //指令名称，例如文本节点，该值设为"text"
this.el = el; //指令对应的DOM元素
this.vm = vm; //指令所属myVue实例
this.exp = exp; //指令对应的值，本例如"number"
this.attr = attr; //绑定的属性值，本例为"innerHTML"
this.update();
}
Watcher.prototype.update = function () {
this.el[this.attr] = this.vm.$data[this.exp];
}
window.onload = function() {
var app = new myVue({
el:'#app',
data: {
number: 0
},
methods: {
increment: function() {
this.number ++;
},
}
})
}
</script>
总结
以上所述是小编给大家介绍的使用Vue如何写一个双向数据绑定(面试常见)，希望对大家有所帮助，如果大家有任何疑问请给我留言，小编会及时回复大家的。在此也非常感谢大家对软件开发网网站的支持！
