ERROR TypeError: Converting circular structure to JSON - Solution
ficheiro.html
<form novalidate #formulario="ngForm">
<pre>{{ formulario.form | json }}</pre>
</form>
Result : ficheiro.html
{
"_hasOwnPendingAsyncValidator": false,
"_parent": null,
"pristine": true,
"touched": false,
"_onDisabledChange": [],
"_rawValidators": null,
"_rawAsyncValidators": null,
"_composedValidatorFn": null,
"_composedAsyncValidatorFn": null,
"controls": {},
"valueChanges": {
"_isScalar": false,
"observers": [],
"closed": false,
"isStopped": false,
"hasError": false,
"thrownError": null,
"__isAsync": false
},
"statusChanges": {
"_isScalar": false,
"observers": [],
"closed": false,
"isStopped": false,
"hasError": false,
"thrownError": null,
"__isAsync": false
},
"status": "VALID",
"value": {},
"errors": null
}