EelemntUI中e-form表单校验的使用以及表单校验的规则

场景

Form 组件提供了表单验证的功能，只需要通过 rules 属性传入约定的验证规则，并将 Form-Item 的 prop 属性设置为需校验的字段名即可。

官方示例代码

<el-form :model="ruleForm" :rules="rules" ref="ruleForm" label-width="100px" class="demo-ruleForm">
  <el-form-item label="活动名称" prop="name">
    <el-input v-model="ruleForm.name"></el-input>
  </el-form-item>
  <el-form-item label="活动区域" prop="region">
    <el-select v-model="ruleForm.region" placeholder="请选择活动区域">
      <el-option label="区域一" value="shanghai"></el-option>
      <el-option label="区域二" value="beijing"></el-option>
    </el-select>
  </el-form-item>
  <el-form-item label="活动时间" required>
    <el-col :span="11">
      <el-form-item prop="date1">
        <el-date-picker type="date" placeholder="选择日期" v-model="ruleForm.date1" style=" 100%;"></el-date-picker>
      </el-form-item>
    </el-col>
    <el-col class="line" :span="2">-</el-col>
    <el-col :span="11">
      <el-form-item prop="date2">
        <el-time-picker placeholder="选择时间" v-model="ruleForm.date2" style=" 100%;"></el-time-picker>
      </el-form-item>
    </el-col>
  </el-form-item>
  <el-form-item label="即时配送" prop="delivery">
    <el-switch v-model="ruleForm.delivery"></el-switch>
  </el-form-item>
  <el-form-item label="活动性质" prop="type">
    <el-checkbox-group v-model="ruleForm.type">
      <el-checkbox label="美食/餐厅线上活动" name="type"></el-checkbox>
      <el-checkbox label="地推活动" name="type"></el-checkbox>
      <el-checkbox label="线下主题活动" name="type"></el-checkbox>
      <el-checkbox label="单纯品牌曝光" name="type"></el-checkbox>
    </el-checkbox-group>
  </el-form-item>
  <el-form-item label="特殊资源" prop="resource">
    <el-radio-group v-model="ruleForm.resource">
      <el-radio label="线上品牌商赞助"></el-radio>
      <el-radio label="线下场地免费"></el-radio>
    </el-radio-group>
  </el-form-item>
  <el-form-item label="活动形式" prop="desc">
    <el-input type="textarea" v-model="ruleForm.desc"></el-input>
  </el-form-item>
  <el-form-item>
    <el-button type="primary" @click="submitForm('ruleForm')">立即创建</el-button>
    <el-button @click="resetForm('ruleForm')">重置</el-button>
  </el-form-item>
</el-form>
<script>
  export default {
    data() {
      return {
        ruleForm: {
          name: '',
          region: '',
          date1: '',
          date2: '',
          delivery: false,
          type: [],
          resource: '',
          desc: ''
        },
        rules: {
          name: [
            { required: true, message: '请输入活动名称', trigger: 'blur' },
            { min: 3, max: 5, message: '长度在 3 到 5 个字符', trigger: 'blur' }
          ],
          region: [
            { required: true, message: '请选择活动区域', trigger: 'change' }
          ],
          date1: [
            { type: 'date', required: true, message: '请选择日期', trigger: 'change' }
          ],
          date2: [
            { type: 'date', required: true, message: '请选择时间', trigger: 'change' }
          ],
          type: [
            { type: 'array', required: true, message: '请至少选择一个活动性质', trigger: 'change' }
          ],
          resource: [
            { required: true, message: '请选择活动资源', trigger: 'change' }
          ],
          desc: [
            { required: true, message: '请填写活动形式', trigger: 'blur' }
          ]
        }
      };
    },
    methods: {
      submitForm(formName) {
        this.$refs[formName].validate((valid) => {
          if (valid) {
            alert('submit!');
          } else {
            console.log('error submit!!');
            return false;
          }
        });
      },
      resetForm(formName) {
        this.$refs[formName].resetFields();
      }
    }
  }
</script>

注：

博客：
https://blog.csdn.net/badao_liumang_qizhi
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实现

首先新建一个form

      <el-form ref="form" :model="form" :rules="rules" label-width="100px">
        <el-row>
          <el-col span="10">
            <el-form-item label="班次编号:" prop="bcbh">
              <el-input v-model="form.bcbh" placeholder="请输入班次编号" />
            </el-form-item>
          </el-col>
          <el-col span="10">
            <el-form-item label="班次名称:" prop="bcmc" label-width="100px">
              <el-input v-model="form.bcmc" placeholder="请输入班次名称" />
            </el-form-item>
          </el-col>
        </el-row>

        <el-row>
          <el-col span="10">
            <el-form-item label="班次类型:" prop="bclx">
              <el-select v-model="form.bclx" placeholder="请选择班次类型" clearable @change="bclxChange">
                <el-option
                  v-for="dict in bclxOptions"
                  :key="dict.dictValue"
                  :label="dict.dictLabel"
                  :value="dict.dictValue"
                />
              </el-select>
            </el-form-item>
          </el-col>
        </el-row>

        <el-row>
          <el-col span="10">
            <el-form-item label="小时数:" prop="xss">
              <el-input-number
                v-model="form.xss"
                :precision="1"
                :step="1"
                :max="24"
                placeholder="请输入小时数"
              ></el-input-number>
            </el-form-item>
          </el-col>
        </el-row>

        <el-row>
          <el-col span="10">
            <el-form-item label="计工数:" prop="jgs" span="10">
              <el-input-number
                v-model="form.jgs"
                :precision="1"
                :step="1"
                :max="24"
                placeholder="请输入计工数"
              ></el-input-number>
            </el-form-item>
          </el-col>
        </el-row>
</el-form>

在form上设置rules验证规则

:rules="rules"

绑定的是一个对象数组，所以在data中

     // 表单校验
      rules: {
        bcbh: [
          { required: true, message: "班次编号不能为空", trigger: "blur" },
        ],
        bcmc: [
          { required: true, message: "班次名称不能为空", trigger: "blur" },
        ],
        bclx: [{ required: true, message: "请选择班次类型", trigger: "blur" }],
        xss: [
          {
            required: true,
            message: "小时数不能为空",
            trigger: "blur",
          },
        ],

        jgs: [{ required: true, message: "计工数不能为空", trigger: "blur" }],
      },

这里的格式是固定的，下面的bcbh要与上面要验证的prop相对应。

这里设置的规则都是要求必填，触发都是失去焦点。

更多校验规则参考如下:

https://github.com/yiminghe/async-validator

下面是英文原文

Usage

Basic usage involves defining a descriptor, assigning it to a schema and passing the object to be validated and a callback function to the validate method of the schema:

import Schema from 'async-validator';
const descriptor = {
  name: {
    type: 'string',
    required: true,
    validator: (rule, value) => value === 'muji',
  },
  age: {
    type: 'number',
    asyncValidator: (rule, value) => {
      return new Promise((resolve, reject) => {
        if (value < 18) {
          reject('too young');  // reject with error message
        } else {
          resolve();
        }
      });
    },
  },
};
const validator = new Schema(descriptor);
validator.validate({ name: 'muji' }, (errors, fields) => {
  if (errors) {
    // validation failed, errors is an array of all errors
    // fields is an object keyed by field name with an array of
    // errors per field
    return handleErrors(errors, fields);
  }
  // validation passed
});

// PROMISE USAGE
validator.validate({ name: 'muji', age: 16 }).then(() => {
  // validation passed or without error message
}).catch(({ errors, fields }) => {
  return handleErrors(errors, fields);
});

API

Validate

function(source, [options], callback): Promise

• source: The object to validate (required).
• options: An object describing processing options for the validation (optional).
• callback: A callback function to invoke when validation completes (required).

The method will return a Promise object like:

• then()，validation passed
• catch({ errors, fields })，validation failed, errors is an array of all errors, fields is an object keyed by field name with an array of

Options

• suppressWarning: Boolean, whether to suppress internal warning about invalid value.

• first: Boolean, Invoke callback when the first validation rule generates an error, no more validation rules are processed. If your validation involves multiple asynchronous calls (for example, database queries) and you only need the first error use this option.

• firstFields: Boolean|String[], Invoke callback when the first validation rule of the specified field generates an error, no more validation rules of the same field are processed. true means all fields.

Rules

Rules may be functions that perform validation.

function(rule, value, callback, source, options)

• rule: The validation rule in the source descriptor that corresponds to the field name being validated. It is always assigned a field property with the name of the field being validated.
• value: The value of the source object property being validated.
• callback: A callback function to invoke once validation is complete. It expects to be passed an array of Error instances to indicate validation failure. If the check is synchronous, you can directly return a false or Error or Error Array.
• source: The source object that was passed to the validate method.
• options: Additional options.
• options.messages: The object containing validation error messages, will be deep merged with defaultMessages.

The options passed to validate or asyncValidate are passed on to the validation functions so that you may reference transient data (such as model references) in validation functions. However, some option names are reserved; if you use these properties of the options object they are overwritten. The reserved properties are messages, exception and error.

import Schema from 'async-validator';
const descriptor = {
  name(rule, value, callback, source, options) {
    const errors = [];
    if (!/^[a-z0-9]+$/.test(value)) {
      errors.push(new Error(
        util.format('%s must be lowercase alphanumeric characters', rule.field),
      ));
    }
    return errors;
  },
};
const validator = new Schema(descriptor);
validator.validate({ name: 'Firstname' }, (errors, fields) => {
  if (errors) {
    return handleErrors(errors, fields);
  }
  // validation passed
});

It is often useful to test against multiple validation rules for a single field, to do so make the rule an array of objects, for example:

const descriptor = {
  email: [
    { type: 'string', required: true, pattern: Schema.pattern.email },
    { 
      validator(rule, value, callback, source, options) {
        const errors = [];
        // test if email address already exists in a database
        // and add a validation error to the errors array if it does
        return errors;
      },
    },
  ],
};

Type

Indicates the type of validator to use. Recognised type values are:

• string: Must be of type string. This is the default type.
• number: Must be of type number.
• boolean: Must be of type boolean.
• method: Must be of type function.
• regexp: Must be an instance of RegExp or a string that does not generate an exception when creating a new RegExp.
• integer: Must be of type number and an integer.
• float: Must be of type number and a floating point number.
• array: Must be an array as determined by Array.isArray.
• object: Must be of type object and not Array.isArray.
• enum: Value must exist in the enum.
• date: Value must be valid as determined by Date
• url: Must be of type url.
• hex: Must be of type hex.
• email: Must be of type email.
• any: Can be any type.

Required

The required rule property indicates that the field must exist on the source object being validated.

Pattern

The pattern rule property indicates a regular expression that the value must match to pass validation.

Range

A range is defined using the min and max properties. For string and array types comparison is performed against the length, for number types the number must not be less than min nor greater than max.

Length

To validate an exact length of a field specify the len property. For string and array types comparison is performed on the length property, for the number type this property indicates an exact match for the number, ie, it may only be strictly equal to len.

If the len property is combined with the min and max range properties, len takes precedence.

Enumerable

Since version 3.0.0 if you want to validate the values 0 or false inside enum types, you have to include them explicitly.

To validate a value from a list of possible values use the enum type with a enum property listing the valid values for the field, for example:

const descriptor = {
  role: { type: 'enum', enum: ['admin', 'user', 'guest'] },
};

Whitespace

It is typical to treat required fields that only contain whitespace as errors. To add an additional test for a string that consists solely of whitespace add a whitespace property to a rule with a value of true. The rule must be a string type.

You may wish to sanitize user input instead of testing for whitespace, see transform for an example that would allow you to strip whitespace.

Deep Rules

If you need to validate deep object properties you may do so for validation rules that are of the object or array type by assigning nested rules to a fields property of the rule.

const descriptor = {
  address: {
    type: 'object',
    required: true,
    fields: {
      street: { type: 'string', required: true },
      city: { type: 'string', required: true },
      zip: { type: 'string', required: true, len: 8, message: 'invalid zip' },
    },
  },
  name: { type: 'string', required: true },
};
const validator = new Schema(descriptor);
validator.validate({ address: {} }, (errors, fields) => {
  // errors for address.street, address.city, address.zip
});

Note that if you do not specify the required property on the parent rule it is perfectly valid for the field not to be declared on the source object and the deep validation rules will not be executed as there is nothing to validate against.

Deep rule validation creates a schema for the nested rules so you can also specify the options passed to the schema.validate() method.

const descriptor = {
  address: {
    type: 'object',
    required: true,
    options: { first: true },
    fields: {
      street: { type: 'string', required: true },
      city: { type: 'string', required: true },
      zip: { type: 'string', required: true, len: 8, message: 'invalid zip' },
    },
  },
  name: { type: 'string', required: true },
};
const validator = new Schema(descriptor);

validator.validate({ address: {} })
  .catch(({ errors, fields }) => {
    // now only errors for street and name    
  });

The parent rule is also validated so if you have a set of rules such as:

const descriptor = {
  roles: {
    type: 'array',
    required: true,
    len: 3,
    fields: {
      0: { type: 'string', required: true },
      1: { type: 'string', required: true },
      2: { type: 'string', required: true },
    },
  },
};

And supply a source object of { roles: ['admin', 'user'] } then two errors will be created. One for the array length mismatch and one for the missing required array entry at index 2.

defaultField

The defaultField property can be used with the array or object type for validating all values of the container. It may be an object or array containing validation rules. For example:

const descriptor = {
  urls: {
    type: 'array',
    required: true,
    defaultField: { type: 'url' },
  },
};

Note that defaultField is expanded to fields, see deep rules.

Transform

Sometimes it is necessary to transform a value before validation, possibly to coerce the value or to sanitize it in some way. To do this add a transform function to the validation rule. The property is transformed prior to validation and re-assigned to the source object to mutate the value of the property in place.

import Schema from 'async-validator';
const descriptor = {
  name: {
    type: 'string',
    required: true,
    pattern: /^[a-z]+$/,
    transform(value) {
      return value.trim();
    },
  },
};
const validator = new Schema(descriptor);
const source = { name: ' user  ' };
validator.validate(source)
  .then(() => assert.equal(source.name, 'user'));

Without the transform function validation would fail due to the pattern not matching as the input contains leading and trailing whitespace, but by adding the transform function validation passes and the field value is sanitized at the same time.

Messages

Depending upon your application requirements, you may need i18n support or you may prefer different validation error messages.

The easiest way to achieve this is to assign a message to a rule:

{ name: { type: 'string', required: true, message: 'Name is required' } }

Message can be any type, such as jsx format.

{ name: { type: 'string', required: true, message: '<b>Name is required</b>' } }

Message can also be a function, e.g. if you use vue-i18n:

{ name: { type: 'string', required: true, message: () => this.$t( 'name is required' ) } }

Potentially you may require the same schema validation rules for different languages, in which case duplicating the schema rules for each language does not make sense.

In this scenario you could just provide your own messages for the language and assign it to the schema:

import Schema from 'async-validator';
const cn = {
  required: '%s 必填',
};
const descriptor = { name: { type: 'string', required: true } };
const validator = new Schema(descriptor);
// deep merge with defaultMessages
validator.messages(cn);
...

If you are defining your own validation functions it is better practice to assign the message strings to a messages object and then access the messages via the options.messages property within the validation function.

asyncValidator

You can customize the asynchronous validation function for the specified field:

const fields = {
  asyncField: {
    asyncValidator(rule, value, callback) {
      ajax({
        url: 'xx',
        value: value,
      }).then(function(data) {
        callback();
      }, function(error) {
        callback(new Error(error));
      });
    },
  },

  promiseField: {
    asyncValidator(rule, value) {
      return ajax({
        url: 'xx',
        value: value,
      });
    },
  },
};

validator

You can custom validate function for specified field:

const fields = {
  field: {
    validator(rule, value, callback) {
      return value === 'test';
    },
    message: 'Value is not equal to "test".',
  },

  field2: {
    validator(rule, value, callback) {
      return new Error(`${value} is not equal to 'test'.`);
    },
  },
 
  arrField: {
    validator(rule, value) {
      return [
        new Error('Message 1'),
        new Error('Message 2'),
      ];
    },
  },
};

FAQ

How to avoid warning

import Schema from 'async-validator';
Schema.warning = function(){};

How to check if it is true

Use enum type passing true as option.

{
  type: 'enum',
  enum: [true],
  message: '',
}