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	| Class | JSONObject | 
|---|
	
		| Name | isNull() | 
	
	
| Examples | 
JSONObject json;
void setup() {
  json = new JSONObject();
  json.setInt("id", 0);
  json.setString("species", null);
  if (json.isNull("species") == true) {
    println("The species is undefined");
  } else {
    println("The ID is " + json.getString("species"));
  }
}
 | 
|---|
		
		| Description | Determines if the value associated with the key is null, that is has no defined value (false) or if it has a value (true). | 
	| Syntax | .isNull(key) | 
|---|
		| Parameters | 
| key | String: A key string. | 
 | 
	| Returns | boolean | 
|---|
Updated on January 21, 2019 10:05:13am EST