added typescript files converted from js files

src/lib/eventHandler.ts

@@ -0,0 +1,40 @@
+type callback = (event: any) => void;
+type target = string | Element | HTMLElement
+
+const eventHandler = {
+    add: function (eventType: string, target: target, selector: string | callback | Element, callback?: callback) {
+        if (typeof selector === 'function' && !callback) {
+            callback = selector;
+            selector = target;
+        }
+        if (typeof target === 'object') {
+
+            target.addEventListener(eventType, function (e) {
+                callback.call(target, e);
+            });
+            return;
+        }
+        let el = document.querySelector(target);
+        if (!el) {
+            return;
+        }
+        el.addEventListener(eventType, function (e) {
+            let element = e.target as HTMLElement;
+            if (element === this && selector === target) {
+                callback.call(element, e);
+                return;
+            }
+            for (; element && element != this; element = element.parentElement) {
+                if (typeof selector === "string" && element.matches(selector)) {
+                    callback.call(element, e);
+                    break;
+                }
+            }
+        });
+    },
+    remove: function (element: target, eventType: string, callback: callback) {
+
+        (<Element>element).removeEventListener(eventType, callback);
+    }
+}
+export default eventHandler;