The `IPAddress` class has a member function `bool fromString(const char *address)`.

```
const char *apipch = "192.168.4.1"
IPAddress apip;

if (apip.fromString(apipch)) { // try to parse into the IPAddress
  Serial.println(apip); // print the parsed IPAddress 
} else {
  Serial.println("unparsable IP");
}
```