diff --git a/dist/calendar/index.js b/dist/calendar/index.js
index 3b7b4540..3b41265c 100644
--- a/dist/calendar/index.js
+++ b/dist/calendar/index.js
@@ -159,7 +159,7 @@ VantComponent({
             return date;
         },
         getInitialDate(defaultDate = null) {
-            const { type, minDate, maxDate } = this.data;
+            const { type, minDate, maxDate, allowSameDay } = this.data;
             const now = getToday().getTime();
             if (type === 'range') {
                 if (!Array.isArray(defaultDate)) {
@@ -167,7 +167,8 @@ VantComponent({
                 }
                 const [startDay, endDay] = defaultDate || [];
                 const start = this.limitDateRange(startDay || now, minDate, getPrevDay(new Date(maxDate)).getTime());
-                const end = this.limitDateRange(endDay || now, getNextDay(new Date(minDate)).getTime());
+                const date = getTime(endDay || now);
+                const end = this.limitDateRange(date, allowSameDay ? date : getNextDay(new Date(minDate)).getTime());
                 return [start, end];
             }
             if (type === 'multiple') {
diff --git a/dist/common/component.js b/dist/common/component.js
index 8528dc0f..938d96ba 100644
--- a/dist/common/component.js
+++ b/dist/common/component.js
@@ -11,6 +11,7 @@ function VantComponent(vantOptions) {
     mapKeys(vantOptions, options, {
         data: 'data',
         props: 'properties',
+        watch: 'observers',
         mixins: 'behaviors',
         methods: 'methods',
         beforeCreate: 'created',
diff --git a/dist/definitions/index.d.ts b/dist/definitions/index.d.ts
index a7cc750a..c4c98f9c 100644
--- a/dist/definitions/index.d.ts
+++ b/dist/definitions/index.d.ts
@@ -15,6 +15,7 @@ export declare type VantComponentOptions<Data extends WechatMiniprogram.Componen
         relations: Record<string, WechatMiniprogram.Component.RelationOption>;
         mixin: string;
     };
+    watch?: Record<string, (...args: any[]) => any>;
     methods?: Methods;
     beforeCreate?: () => void;
     created?: () => void;
diff --git a/dist/dropdown-item/index.js b/dist/dropdown-item/index.js
index 2934ce3a..e0d27ebb 100644
--- a/dist/dropdown-item/index.js
+++ b/dist/dropdown-item/index.js
@@ -26,6 +26,10 @@ VantComponent({
             observer: 'rerender',
         },
         popupStyle: String,
+        useBeforeToggle: {
+            type: Boolean,
+            value: false,
+        },
     },
     data: {
         transition: true,
@@ -77,7 +81,6 @@ VantComponent({
             }
         },
         toggle(show, options = {}) {
-            var _a;
             const { showPopup } = this.data;
             if (typeof show !== 'boolean') {
                 show = !showPopup;
@@ -85,19 +88,37 @@ VantComponent({
             if (show === showPopup) {
                 return;
             }
-            this.setData({
-                transition: !options.immediate,
-                showPopup: show,
-            });
-            if (show) {
-                (_a = this.parent) === null || _a === void 0 ? void 0 : _a.getChildWrapperStyle().then((wrapperStyle) => {
-                    this.setData({ wrapperStyle, showWrapper: true });
-                    this.rerender();
+            this.onBeforeToggle(show).then((status) => {
+                var _a;
+                if (!status) {
+                    return;
+                }
+                this.setData({
+                    transition: !options.immediate,
+                    showPopup: show,
                 });
+                if (show) {
+                    (_a = this.parent) === null || _a === void 0 ? void 0 : _a.getChildWrapperStyle().then((wrapperStyle) => {
+                        this.setData({ wrapperStyle, showWrapper: true });
+                        this.rerender();
+                    });
+                }
+                else {
+                    this.rerender();
+                }
+            });
+        },
+        onBeforeToggle(status) {
+            const { useBeforeToggle } = this.data;
+            if (!useBeforeToggle) {
+                return Promise.resolve(true);
             }
-            else {
-                this.rerender();
-            }
+            return new Promise((resolve) => {
+                this.$emit('before-toggle', {
+                    status,
+                    callback: (value) => resolve(value),
+                });
+            });
         },
     },
 });
diff --git a/dist/field/index.js b/dist/field/index.js
index 35627a2b..7d982075 100644
--- a/dist/field/index.js
+++ b/dist/field/index.js
@@ -22,6 +22,9 @@ VantComponent({
         }, clearIcon: {
             type: String,
             value: 'clear',
+        }, extraEventParams: {
+            type: Boolean,
+            value: false,
         } }),
     data: {
         focused: false,
@@ -37,7 +40,7 @@ VantComponent({
             const { value = '' } = event.detail || {};
             this.value = value;
             this.setShowClear();
-            this.emitChange();
+            this.emitChange(event.detail);
         },
         onFocus(event) {
             this.focused = true;
@@ -60,7 +63,7 @@ VantComponent({
             this.value = '';
             this.setShowClear();
             nextTick(() => {
-                this.emitChange();
+                this.emitChange({ value: '' });
                 this.$emit('clear', '');
             });
         },
@@ -76,7 +79,7 @@ VantComponent({
             if (value === '') {
                 this.setData({ innerValue: '' });
             }
-            this.emitChange();
+            this.emitChange({ value });
         },
         onLineChange(event) {
             this.$emit('linechange', event.detail);
@@ -84,11 +87,13 @@ VantComponent({
         onKeyboardHeightChange(event) {
             this.$emit('keyboardheightchange', event.detail);
         },
-        emitChange() {
-            this.setData({ value: this.value });
+        emitChange(detail) {
+            const { extraEventParams } = this.data;
+            this.setData({ value: detail.value });
             nextTick(() => {
-                this.$emit('input', this.value);
-                this.$emit('change', this.value);
+                const data = extraEventParams ? detail : detail.value;
+                this.$emit('input', data);
+                this.$emit('change', data);
             });
         },
         setShowClear() {
diff --git a/dist/field/types.d.ts b/dist/field/types.d.ts
new file mode 100644
index 00000000..357ccbe4
--- /dev/null
+++ b/dist/field/types.d.ts
@@ -0,0 +1,8 @@
+export interface InputDetails {
+    /** 输入框内容 */
+    value: string;
+    /** 光标位置 */
+    cursor?: number;
+    /** keyCode 为键值 (目前工具还不支持返回keyCode参数) `2.1.0` 起支持 */
+    keyCode?: number;
+}
diff --git a/dist/field/types.js b/dist/field/types.js
new file mode 100644
index 00000000..cb0ff5c3
--- /dev/null
+++ b/dist/field/types.js
@@ -0,0 +1 @@
+export {};
diff --git a/dist/stepper/index.js b/dist/stepper/index.js
index 08076d7e..5af81a93 100644
--- a/dist/stepper/index.js
+++ b/dist/stepper/index.js
@@ -16,7 +16,6 @@ VantComponent({
     props: {
         value: {
             type: null,
-            observer: 'observeValue',
         },
         integer: {
             type: Boolean,
@@ -66,6 +65,11 @@ VantComponent({
     data: {
         currentValue: '',
     },
+    watch: {
+        value() {
+            this.observeValue();
+        },
+    },
     created() {
         this.setData({
             currentValue: this.format(this.data.value),
@@ -73,10 +77,8 @@ VantComponent({
     },
     methods: {
         observeValue() {
-            const { value, currentValue } = this.data;
-            if (!equal(value, currentValue)) {
-                this.setData({ currentValue: this.format(value) });
-            }
+            const { value } = this.data;
+            this.setData({ currentValue: this.format(value) });
         },
         check() {
             const val = this.format(this.data.currentValue);
diff --git a/lib/calendar/index.js b/lib/calendar/index.js
index 31989f07..3baa5f0b 100644
--- a/lib/calendar/index.js
+++ b/lib/calendar/index.js
@@ -180,7 +180,7 @@ var getTime = function (date) {
         getInitialDate: function (defaultDate) {
             var _this = this;
             if (defaultDate === void 0) { defaultDate = null; }
-            var _a = this.data, type = _a.type, minDate = _a.minDate, maxDate = _a.maxDate;
+            var _a = this.data, type = _a.type, minDate = _a.minDate, maxDate = _a.maxDate, allowSameDay = _a.allowSameDay;
             var now = (0, utils_1.getToday)().getTime();
             if (type === 'range') {
                 if (!Array.isArray(defaultDate)) {
@@ -188,7 +188,8 @@ var getTime = function (date) {
                 }
                 var _b = defaultDate || [], startDay = _b[0], endDay = _b[1];
                 var start = this.limitDateRange(startDay || now, minDate, (0, utils_1.getPrevDay)(new Date(maxDate)).getTime());
-                var end = this.limitDateRange(endDay || now, (0, utils_1.getNextDay)(new Date(minDate)).getTime());
+                var date = getTime(endDay || now);
+                var end = this.limitDateRange(date, allowSameDay ? date : (0, utils_1.getNextDay)(new Date(minDate)).getTime());
                 return [start, end];
             }
             if (type === 'multiple') {
diff --git a/lib/common/component.js b/lib/common/component.js
index f1ab5c91..66da00e0 100644
--- a/lib/common/component.js
+++ b/lib/common/component.js
@@ -14,6 +14,7 @@ function VantComponent(vantOptions) {
     mapKeys(vantOptions, options, {
         data: 'data',
         props: 'properties',
+        watch: 'observers',
         mixins: 'behaviors',
         methods: 'methods',
         beforeCreate: 'created',
diff --git a/lib/definitions/index.d.ts b/lib/definitions/index.d.ts
index a7cc750a..c4c98f9c 100644
--- a/lib/definitions/index.d.ts
+++ b/lib/definitions/index.d.ts
@@ -15,6 +15,7 @@ export declare type VantComponentOptions<Data extends WechatMiniprogram.Componen
         relations: Record<string, WechatMiniprogram.Component.RelationOption>;
         mixin: string;
     };
+    watch?: Record<string, (...args: any[]) => any>;
     methods?: Methods;
     beforeCreate?: () => void;
     created?: () => void;
diff --git a/lib/dropdown-item/index.js b/lib/dropdown-item/index.js
index eb1bb601..0dd143d9 100644
--- a/lib/dropdown-item/index.js
+++ b/lib/dropdown-item/index.js
@@ -28,6 +28,10 @@ var component_1 = require("../common/component");
             observer: 'rerender',
         },
         popupStyle: String,
+        useBeforeToggle: {
+            type: Boolean,
+            value: false,
+        },
     },
     data: {
         transition: true,
@@ -81,7 +85,6 @@ var component_1 = require("../common/component");
         },
         toggle: function (show, options) {
             var _this = this;
-            var _a;
             if (options === void 0) { options = {}; }
             var showPopup = this.data.showPopup;
             if (typeof show !== 'boolean') {
@@ -90,19 +93,38 @@ var component_1 = require("../common/component");
             if (show === showPopup) {
                 return;
             }
-            this.setData({
-                transition: !options.immediate,
-                showPopup: show,
-            });
-            if (show) {
-                (_a = this.parent) === null || _a === void 0 ? void 0 : _a.getChildWrapperStyle().then(function (wrapperStyle) {
-                    _this.setData({ wrapperStyle: wrapperStyle, showWrapper: true });
-                    _this.rerender();
+            this.onBeforeToggle(show).then(function (status) {
+                var _a;
+                if (!status) {
+                    return;
+                }
+                _this.setData({
+                    transition: !options.immediate,
+                    showPopup: show,
                 });
+                if (show) {
+                    (_a = _this.parent) === null || _a === void 0 ? void 0 : _a.getChildWrapperStyle().then(function (wrapperStyle) {
+                        _this.setData({ wrapperStyle: wrapperStyle, showWrapper: true });
+                        _this.rerender();
+                    });
+                }
+                else {
+                    _this.rerender();
+                }
+            });
+        },
+        onBeforeToggle: function (status) {
+            var _this = this;
+            var useBeforeToggle = this.data.useBeforeToggle;
+            if (!useBeforeToggle) {
+                return Promise.resolve(true);
             }
-            else {
-                this.rerender();
-            }
+            return new Promise(function (resolve) {
+                _this.$emit('before-toggle', {
+                    status: status,
+                    callback: function (value) { return resolve(value); },
+                });
+            });
         },
     },
 });
diff --git a/lib/field/index.js b/lib/field/index.js
index 5e93c3a0..7bb7393a 100644
--- a/lib/field/index.js
+++ b/lib/field/index.js
@@ -35,6 +35,9 @@ var props_1 = require("./props");
         }, clearIcon: {
             type: String,
             value: 'clear',
+        }, extraEventParams: {
+            type: Boolean,
+            value: false,
         } }),
     data: {
         focused: false,
@@ -50,7 +53,7 @@ var props_1 = require("./props");
             var _a = (event.detail || {}).value, value = _a === void 0 ? '' : _a;
             this.value = value;
             this.setShowClear();
-            this.emitChange();
+            this.emitChange(event.detail);
         },
         onFocus: function (event) {
             this.focused = true;
@@ -74,7 +77,7 @@ var props_1 = require("./props");
             this.value = '';
             this.setShowClear();
             (0, utils_1.nextTick)(function () {
-                _this.emitChange();
+                _this.emitChange({ value: '' });
                 _this.$emit('clear', '');
             });
         },
@@ -90,7 +93,7 @@ var props_1 = require("./props");
             if (value === '') {
                 this.setData({ innerValue: '' });
             }
-            this.emitChange();
+            this.emitChange({ value: value });
         },
         onLineChange: function (event) {
             this.$emit('linechange', event.detail);
@@ -98,12 +101,14 @@ var props_1 = require("./props");
         onKeyboardHeightChange: function (event) {
             this.$emit('keyboardheightchange', event.detail);
         },
-        emitChange: function () {
+        emitChange: function (detail) {
             var _this = this;
-            this.setData({ value: this.value });
+            var extraEventParams = this.data.extraEventParams;
+            this.setData({ value: detail.value });
             (0, utils_1.nextTick)(function () {
-                _this.$emit('input', _this.value);
-                _this.$emit('change', _this.value);
+                var data = extraEventParams ? detail : detail.value;
+                _this.$emit('input', data);
+                _this.$emit('change', data);
             });
         },
         setShowClear: function () {
diff --git a/lib/field/types.d.ts b/lib/field/types.d.ts
new file mode 100644
index 00000000..357ccbe4
--- /dev/null
+++ b/lib/field/types.d.ts
@@ -0,0 +1,8 @@
+export interface InputDetails {
+    /** 输入框内容 */
+    value: string;
+    /** 光标位置 */
+    cursor?: number;
+    /** keyCode 为键值 (目前工具还不支持返回keyCode参数) `2.1.0` 起支持 */
+    keyCode?: number;
+}
diff --git a/lib/field/types.js b/lib/field/types.js
new file mode 100644
index 00000000..c8ad2e54
--- /dev/null
+++ b/lib/field/types.js
@@ -0,0 +1,2 @@
+"use strict";
+Object.defineProperty(exports, "__esModule", { value: true });
diff --git a/lib/stepper/index.js b/lib/stepper/index.js
index 1674b4f1..d9694e22 100644
--- a/lib/stepper/index.js
+++ b/lib/stepper/index.js
@@ -29,7 +29,6 @@ function equal(value1, value2) {
     props: {
         value: {
             type: null,
-            observer: 'observeValue',
         },
         integer: {
             type: Boolean,
@@ -79,6 +78,11 @@ function equal(value1, value2) {
     data: {
         currentValue: '',
     },
+    watch: {
+        value: function () {
+            this.observeValue();
+        },
+    },
     created: function () {
         this.setData({
             currentValue: this.format(this.data.value),
@@ -86,10 +90,8 @@ function equal(value1, value2) {
     },
     methods: {
         observeValue: function () {
-            var _a = this.data, value = _a.value, currentValue = _a.currentValue;
-            if (!equal(value, currentValue)) {
-                this.setData({ currentValue: this.format(value) });
-            }
+            var value = this.data.value;
+            this.setData({ currentValue: this.format(value) });
         },
         check: function () {
             var val = this.format(this.data.currentValue);