feat(Form): add validate-trigger prop

src/field/index.js

@@ -64,6 +64,7 @@ export default createComponent({
   watch: {
     value() {
       this.resetValidation();
+      this.validateWithTrigger('onChange');
       this.$nextTick(this.adjustSize);
     },
   },
@@ -158,8 +159,8 @@ export default createComponent({
       });
     },
 
-    runRules() {
+    runRules(rules) {
-      return this.rules.reduce(
+      return rules.reduce(
         (promise, rule) =>
           promise.then(() => {
             if (this.validateMessage) {
@@ -183,13 +184,13 @@ export default createComponent({
       );
     },
 
-    validate() {
+    validate(rules = this.rules) {
       return new Promise(resolve => {
-        if (!this.rules) {
+        if (!rules) {
           resolve();
         }
 
-        this.runRules().then(() => {
+        this.runRules(rules).then(() => {
           if (this.validateMessage) {
             resolve({
               name: this.name,
@@ -202,6 +203,21 @@ export default createComponent({
       });
     },
 
+    validateWithTrigger(trigger) {
+      if (this.vanForm && this.rules) {
+        const defaultTrigger = this.vanForm.validateTrigger === trigger;
+        const rules = this.rules.filter(rule => {
+          if (rule.trigger) {
+            return rule.trigger === trigger;
+          }
+
+          return defaultTrigger;
+        });
+
+        this.validate(rules);
+      }
+    },
+
     resetValidation() {
       if (this.validateMessage) {
         this.validateMessage = '';
@@ -269,6 +285,7 @@ export default createComponent({
     onBlur(event) {
       this.focused = false;
       this.$emit('blur', event);
+      this.validateWithTrigger('onBlur');
       resetScroll();
     },
 

src/form/README.md

@@ -411,6 +411,7 @@ export default {
 | error-message-align | Error message align, can be set to `center` `right` | *string* | `left` |
 | colon | Whether to display `:` after label | *boolean* | *false* |
 | validate-first | Whether to stop the validation when a rule fails | *boolean* | `false` |
+| validate-trigger `v2.5.2` | When to validate the form，can be set to `onChange`、`onSubmit` | *string* | `onBlur` |
 
 ### Events
 

src/form/README.zh-CN.md

@@ -443,6 +443,7 @@ export default {
 | error-message-align | 错误提示文案对齐方式，可选值为 `center` `right` | *string* | `left` |
 | colon | 是否在 label 后面添加冒号 | *boolean* | *false* |
 | validate-first | 是否在某一项校验不通过时停止校验 | *boolean* | `false` |
+| validate-trigger `v2.5.2` | 表单校验触发时机，可选值为`onChange`、`onSubmit` | *string* | `onBlur` |
 
 > 表单项的 API 参见：[Field 组件](#/zh-CN/field#api)
 

src/form/index.js

@@ -10,6 +10,10 @@ export default createComponent({
     inputAlign: String,
     validateFirst: Boolean,
     errorMessageAlign: String,
+    validateTrigger: {
+      type: String,
+      default: 'onBlur',
+    },
   },
 
   provide() {

src/form/test/props.spec.js

@@ -1,3 +1,4 @@
+import { later } from '../../../test';
 import { mountForm, submitForm, getSimpleRules } from './shared';
 
 test('rules prop - execute order', async () => {
@@ -167,3 +168,54 @@ test('error-message-align prop', () => {
   });
   expect(wrapper).toMatchSnapshot();
 });
+
+test('validate-trigger - onBlur', async () => {
+  const wrapper = mountForm({
+    template: `
+      <van-form ref="form">
+        <van-field name="A" :rules="rulesA" value="" />
+      </van-form>
+    `,
+    data: getSimpleRules,
+  });
+
+  const input = wrapper.find('input');
+
+  input.trigger('input');
+  await later();
+  expect(wrapper.contains('.van-field__error-message')).toBeFalsy();
+
+  input.trigger('blur');
+  await later();
+  expect(wrapper.contains('.van-field__error-message')).toBeTruthy();
+});
+
+test('validate-trigger - onChange', async () => {
+  const wrapper = mountForm({
+    template: `
+      <van-form validate-trigger="onChange" ref="form">
+        <van-field v-model="value" name="A" :rules="rulesA" />
+      </van-form>
+    `,
+    data() {
+      return {
+        ...getSimpleRules(),
+        value: '',
+      };
+    },
+  });
+
+  const input = wrapper.find('input');
+
+  input.trigger('blur');
+  await later();
+  expect(wrapper.contains('.van-field__error-message')).toBeFalsy();
+
+  wrapper.setData({ value: '1' });
+  await later();
+  expect(wrapper.contains('.van-field__error-message')).toBeFalsy();
+
+  wrapper.setData({ value: '' });
+  await later();
+  expect(wrapper.contains('.van-field__error-message')).toBeTruthy();
+});

src/mixins/field.js

@@ -7,15 +7,20 @@ export const FieldMixin = {
 
   watch: {
     value() {
-      if (this.vanField) {
+      const field = this.vanField;
-        this.vanField.resetValidation();
+
+      if (field) {
+        field.resetValidation();
+        field.validateWithTrigger('onChange');
       }
     },
   },
 
   created() {
-    if (this.vanField && !this.vanField.children) {
+    const field = this.vanField;
-      this.vanField.children = this;
+
+    if (field && !field.children) {
+      field.children = this;
     }
   },
 };