Vue.js, Props Validation

Properties validation in Vue.js allows you to validate the props supplied to a component. This may be accomplished by utilizing the props option in the options object of the component. You can define the type of prop and whether or not it is necessary.

Vue.js, Props Validation Example

For example, if you have a component called “MyComponent” that requires a prop called “message” that should be a string and is necessary, you may verify it as follows:

props: {
  message: {
    type: String,
    required: true
  }
}

You can also use the validator function to provide more complex validation logic. The validator function takes the prop’s value as its argument and should return a boolean indicating whether the value is valid or not.

props: {
  message: {
    validator: function(value) {
      return value.length > 10
    }
  }
}

You can also use the default property to set a default value for a prop.

props: {
  message: {
    type: String,
    default: 'Hello World'
  }
}

It’s important to note that Vue will not throw an error when a prop fails validation. Instead, it will emit a warning in the browser’s JavaScript console.