Useful helpers - evaluating form's defaults
#### evalDefaults
Let's look one more on the example from previous [section][simple-validation], in particular on the `getInitialState` method:
```javascript
var FG = window.FormGenerator
, t = window.FormGenerator.tools;
...
var App = React.createClass({
getInitialState: function () {
return {
value: t.evalDefaults( meta ), // this line
errors: {}
};
}
```
Here `evalDefaults` helper allow us to get initial value of the form.
This function takes form's metadata, and brings together all `defaultValue` properties in the `fields` section.
#### validateForm
Another usefull helper is `validateForm`. It takes form's meta and
value and returns information about form's validations errors in the
same format, which is required by property `errors` of GeneratedForm.
So we can rewrite our example like this:
```javascript
var FG = window.FormGenerator
, t = window.FormGenerator.tools
, GeneratedForm = FG({})
, validateForm = GeneratedForm.validateForm;
var App = React.createClass({
getInitialState: function () {
var value = t.evalDefaults( meta );
return {
value: value,
errors: validateForm( meta, value ) // this line
};
},
...
render: function() {
return ();
}
```
Here is JSFiddle example with default value and errors:
Of course, it's not very useful to show validation errors before user
even starting to type anything. So in the [next section][simple-events-routing] you will see more real-like example of `validateForm` using.
[simple-validation]: http://react-form-generator.readthedocs.org/en/latest/basic/simple-validation/
[simple-events-routing]: http://react-form-generator.readthedocs.org/en/latest/basic/simple-events-routing/