From af4b6b23c546ad2a97a21cb9535aea5d5568182d Mon Sep 17 00:00:00 2001
From: Joseph Cheung <josephz2314@hotmail.com>
Date: Wed, 14 Nov 2018 10:32:37 +0800
Subject: [PATCH 1/2] finished

---
 lib/index.js | 25 +++++++++++++++++++++++++
 1 file changed, 25 insertions(+)

diff --git a/lib/index.js b/lib/index.js
index 8d2deb0..c0a1e31 100644
--- a/lib/index.js
+++ b/lib/index.js
@@ -3,14 +3,39 @@
   class Delegator {
     constructor (selector/* root选择器 */) {
       // TODO
+      this.root = doc.querySelector(selector);
+      this.delegatedListeners = {};
+      this.cache = {};
+    }
+
+    cachedQuerySelector(selector) {
+      selector = selector.replace(/^\s+(.*?)\s+$/g, '$1');
+      if (this.cache[selector]) return this.cache[selector];
+      var item = doc.querySelector(selector);
+      this.cache[selector] = item;
+      return item;
     }
 
     on (event/* 绑定事件 */, selector/* 触发事件节点对应选择器 */, fn/* 出发函数 */) {
       // TODO
+      var item = this.cachedQuerySelector(selector);
+      if (!this.delegatedListeners[event]) this.delegatedListeners[event] = [];
+      let delegated = fn.bind(item);
+      this.delegatedListeners[event].push({
+        target: item,
+        event: delegated
+      })
+      item.addEventListener(event, delegated);
+      return this
     }
 
     destroy () {
       // TODO
+      Object.keys(this.delegatedListeners).forEach(eventNm => {
+        this.delegatedListeners[eventNm].forEach(item => {
+          item.target.removeEventListener(eventNm, item.event);
+        })
+      })
     }
   }
 

From 3fa29a7beb3bc9911d584d926236f367f14d3eb6 Mon Sep 17 00:00:00 2001
From: Joseph Cheung <josephz2314@hotmail.com>
Date: Wed, 14 Nov 2018 22:57:45 +0800
Subject: [PATCH 2/2] =?UTF-8?q?=E8=BF=99=E4=B8=8B=E6=98=AF=E4=BB=A3?=
 =?UTF-8?q?=E7=90=86=E4=BA=86=E5=8F=AD?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 lib/index.js    | 50 +++++++++++++++++++++++++++++++------------------
 lib/polyfill.js | 14 ++++++++++++++
 2 files changed, 46 insertions(+), 18 deletions(-)
 create mode 100644 lib/polyfill.js

diff --git a/lib/index.js b/lib/index.js
index c0a1e31..870c36b 100644
--- a/lib/index.js
+++ b/lib/index.js
@@ -5,36 +5,50 @@
       // TODO
       this.root = doc.querySelector(selector);
       this.delegatedListeners = {};
-      this.cache = {};
     }
 
-    cachedQuerySelector(selector) {
-      selector = selector.replace(/^\s+(.*?)\s+$/g, '$1');
-      if (this.cache[selector]) return this.cache[selector];
-      var item = doc.querySelector(selector);
-      this.cache[selector] = item;
-      return item;
+    delegator (eventNm) {
+      return (e, ...args) => {
+        var event = e || window.event;
+        // console.log(e);
+        var i = 0, len = event.path.length;
+        while (i < len) {
+          var target = event.path[i];
+          this.delegatedListeners[eventNm].listeners.forEach(item => {
+            if (target.matches(item.selector)) {
+              item.fn.call(target, e, ...args);
+            }
+          })
+          if (target === this.root) return
+          i++;
+        }
+      }
     }
 
     on (event/* 绑定事件 */, selector/* 触发事件节点对应选择器 */, fn/* 出发函数 */) {
-      // TODO
-      var item = this.cachedQuerySelector(selector);
-      if (!this.delegatedListeners[event]) this.delegatedListeners[event] = [];
-      let delegated = fn.bind(item);
-      this.delegatedListeners[event].push({
-        target: item,
-        event: delegated
+      // 字符串处理selector
+      selector = selector.replace(/^\s+(.*?)\s+$/g, '$1');
+
+      if (!this.delegatedListeners[event]) {
+        let delegator = this.delegator(event);
+        this.delegatedListeners[event] = {
+          delegator,
+          listeners: []
+        }
+        this.root.addEventListener(event, delegator);
+      };
+      this.delegatedListeners[event].listeners.push({
+        selector,
+        fn
       })
-      item.addEventListener(event, delegated);
+
       return this
     }
 
     destroy () {
       // TODO
       Object.keys(this.delegatedListeners).forEach(eventNm => {
-        this.delegatedListeners[eventNm].forEach(item => {
-          item.target.removeEventListener(eventNm, item.event);
-        })
+          this.root.removeEventListener(eventNm, this.delegatedListeners[eventNm].delegator);
       })
     }
   }
diff --git a/lib/polyfill.js b/lib/polyfill.js
new file mode 100644
index 0000000..3cc5a48
--- /dev/null
+++ b/lib/polyfill.js
@@ -0,0 +1,14 @@
+if (!Element.prototype.matches) {
+    Element.prototype.matches =
+        Element.prototype.matchesSelector ||
+        Element.prototype.mozMatchesSelector ||
+        Element.prototype.msMatchesSelector ||
+        Element.prototype.oMatchesSelector ||
+        Element.prototype.webkitMatchesSelector ||
+        function(s) {
+            var matches = (this.document || this.ownerDocument).querySelectorAll(s),
+            i = matches.length;
+            while (--i >= 0 && matches.item(i) !== this) {}
+            return i > -1;            
+    };
+}
\ No newline at end of file