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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.
Returnsboolean
Updated on January 1, 2021 03:38:09am EST

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