摘要：原文地址的博客點擊在線嘗試一下最終效果如下構造器構造一個對象，包含基本的，，初始化編譯器用于解析綁定到輸入框和下拉框的和元素的點擊事件。

原文地址：Bougie的博客

點擊在線嘗試一下

最終效果如下：

構造一個TinyVue對象，包含基本的el，data，methods

class TinyVue{
    constructor({el, data, methods}){
        this.$data = data
        this.$el = document.querySelector(el)
        this.$methods = methods
        // 初始化
        this._compile()
        this._updater()
        this._watcher()
    }
}

用于解析綁定到輸入框和下拉框的v-model和元素的點擊事件@click。
先創建一個函數用來載入事件：

// el為元素tagName，attr為元素屬性（v-model，@click）
_initEvents(el, attr, callBack) {
    this.$el.querySelectorAll(el).forEach(i => {
        if(i.hasAttribute(attr)) {
            let key = i.getAttribute(attr)
            callBack(i, key)
        }
    })
}

this._initEvents("input, textarea", "v-model", (i, key) => {
    i.addEventListener("input", () => {
        Object.assign(this.$data, {[key]: i.value})
    })
})

this._initEvents("select", "v-model", (i, key) => {
    i.addEventListener("change", () => Object.assign(this.$data, {[key]: i.options[i.options.selectedIndex].value}))
})

點擊事件對應的是methods中的事件

this._initEvents("*", "@click", (i, key) => {
    i.addEventListener("click", () => this.$methods[key].bind(this.$data)())
})

同理先創建公共函數來處理不同元素中的視圖，包括input、textarea的value，select的選擇值，div的innerHTML

_initView(el, attr, callBack) {
    this.$el.querySelectorAll(el, attr, callBack).forEach(i => {
        if(i.hasAttribute(attr)) {
            let key = i.getAttribute(attr),
                data = this.$data[key]
            callBack(i, key, data)
        }
    })
}

this._initView("input, textarea", "v-model", (i, key, data) => {
    i.value = data
})

this._initView("select", "v-model", (i, key, data) => {
    i.querySelectorAll("option").forEach(v => {
        if(v.value == data) v.setAttribute("selected", true)
        else v.removeAttribute("selected")
    })
})

這里實現方法有點low，僅想到正則替換{{text}}

let regExpInner = /{{ *([w_-]+) *}}/g
this.$el.querySelectorAll("*").forEach(i => {
    let replaceList = i.innerHTML.match(regExpInner) || (i.hasAttribute("vueID") && i.getAttribute("vueID").match(regExpInner))
    if(replaceList) {
        if(!i.hasAttribute("vueID")) {
            i.setAttribute("vueID", i.innerHTML)
        }
        i.innerHTML = i.getAttribute("vueID")
        replaceList.forEach(v => {
            let key = v.slice(2, v.length - 2)
            i.innerHTML = i.innerHTML.replace(v, this.$data[key])
        })
    }
})

數據變化之后更新視圖

_watcher(data = this.$data) {
    let that = this
    Object.keys(data).forEach(i => {
        let value = data[i]
        Object.defineProperty(data, i, {
            enumerable: true,
            configurable: true,
            get: function () {
                return value;
            },
            set: function (newVal) {
                if (value !== newVal) {
                    value = newVal;
                    that._updater()
                }
            }
        })
    })
}

    

    

    

    加一
    
您輸入的是：{{text1}}+{{text2}}+{{text3}}
    
        Volvo
        Saab
    
    
        Volvo
        Saab
    
    
您選擇了：{{select}}

class TinyVue{
    constructor({el, data, methods}){
        this.$data = data
        this.$el = document.querySelector(el)
        this.$methods = methods
        this._compile()
        this._updater()
        this._watcher()
    }
    _watcher(data = this.$data) {
        let that = this
        Object.keys(data).forEach(i => {
            let value = data[i]
            Object.defineProperty(data, i, {
                enumerable: true,
                configurable: true,
                get: function () {
                    return value;
                },
                set: function (newVal) {
                    if (value !== newVal) {
                        value = newVal;
                        that._updater()
                    }
                }
            })
        })
    }
    _initEvents(el, attr, callBack) {
        this.$el.querySelectorAll(el).forEach(i => {
            if(i.hasAttribute(attr)) {
                let key = i.getAttribute(attr)
                callBack(i, key)
            }
        })
    }
    _initView(el, attr, callBack) {
        this.$el.querySelectorAll(el, attr, callBack).forEach(i => {
            if(i.hasAttribute(attr)) {
                let key = i.getAttribute(attr),
                    data = this.$data[key]
                callBack(i, key, data)
            }
        })
    }
    _updater() {
        this._initView("input, textarea", "v-model", (i, key, data) => {
            i.value = data
        })
        this._initView("select", "v-model", (i, key, data) => {
            i.querySelectorAll("option").forEach(v => {
                if(v.value == data) v.setAttribute("selected", true)
                else v.removeAttribute("selected")
            })
        })
        let regExpInner = /{{ *([w_-]+) *}}/g
        this.$el.querySelectorAll("*").forEach(i => {
            let replaceList = i.innerHTML.match(regExpInner) || (i.hasAttribute("vueID") && i.getAttribute("vueID").match(regExpInner))
            if(replaceList) {
                if(!i.hasAttribute("vueID")) {
                    i.setAttribute("vueID", i.innerHTML)
                }
                i.innerHTML = i.getAttribute("vueID")
                replaceList.forEach(v => {
                    let key = v.slice(2, v.length - 2)
                    i.innerHTML = i.innerHTML.replace(v, this.$data[key])
                })
            }
        })
    }
    _compile() {
        this._initEvents("*", "@click", (i, key) => {
            i.addEventListener("click", () => this.$methods[key].bind(this.$data)())
        })
        this._initEvents("input, textarea", "v-model", (i, key) => {
            i.addEventListener("input", () => {
                Object.assign(this.$data, {[key]: i.value})
            })
        })
        this._initEvents("select", "v-model", (i, key) => {
            i.addEventListener("change", () => Object.assign(this.$data, {[key]: i.options[i.options.selectedIndex].value}))
        })
    }
}