Vuetify custom validation for confirm password

Question

I am working on Vue.js template and on the sign up page, I need to compare password while user signup so, I added custom validation rule like the following code:

<v-text-field 
    label="Password" 
    v-model="password" 
    :rules="passwordRules" 
    type="password" 
    required
></v-text-field>
<v-text-field 
    label="Confirm Password" 
    v-model="confirmPassword" 
    :rules="[confirmPasswordRules,passwordConfirmationRule]"
    type="password" 
    required
></v-text-field>

script:

data() {
    return {
        password: "",
        confirmPassword: "",
        passwordRules: [v => !!v || "Password is required"],
        confirmPasswordRules: [v => !!v || "Password is required"],
    };
},

Compare password method in computed:

computed: {
    passwordConfirmationRule() {
        return () => (this.password === this.confirmPassword) || 'Password must match'
    },
}

I use the computed method for confirm password its working fine and compare the password perfectly but it shows error in console [Vuetify] Rules should return a string or boolean, received 'object' instead so how can I solve this ??

Answer 1

You're getting the error message because the rules property of the "Confirm Password" input doesn't contain a one-dimensional array containing the rules, but instead contains confirmPasswordRules which is an array itself plus the passwordConfirmationRule rule.

So essentially this

:rules="[confirmPasswordRules, passwordConfirmationRule]"

contains this:

:rules="[[v => !!v || "Password is required"], (this.password === this.confirmPassword) || 'Password must match']"

You want all of the rules to be contained in a single array instead. You can use the concat method to add the passwordConfirmationRule to the confirmPasswordRules array like this:

:rules="confirmPasswordRules.concat(passwordConfirmationRule)" 

I've created a Codepen to show that this works here.

Answer 2

you can use

template :

<v-text-field
  v-model="password"
  label="Password"
  name="password"
  prepend-icon="mdi-lock"
  type="password"
  :rules="passwordRules"
/>

<v-text-field
  v-model="confirmPassword"
  label="Confirm Password"
  name="confirmPassword"
  prepend-icon="mdi-lock"
  type="password"
  :rules="confirmPasswordRules"
/>

script:

data() {
    return {
      password: '',
      confirmPassword: '',
      passwordRules: [
        (value) => !!value || 'Please type password.',
        (value) => (value && value.length >= 6) || 'minimum 6 characters',
      ],
      confirmPasswordRules: [
        (value) => !!value || 'type confirm password',
        (value) =>
          value === this.password || 'The password confirmation does not match.',
      ],
    }
},