Methods
getData(key) → {string|object}
Gets the data value for the given key, or gets a hash containing all key values, if a key was not provided.
Note: If a hash is returned, this will be a new object each time it is called. Adding new properties to the returned hash will not add data to the object.
Note: The returned data is not mutated or sanitized, which could lead to a security vulnerability if not sanitized properly before use.
Parameters:
Name | Type | Description |
---|---|---|
key |
string |
The key for which to get the data value. |
Throws:
-
If the
key
argument is null or otherwise not a string. -
- Type
- Error
Returns:
- If a key argument was provided, it returns the associated value.
- If a key argument was provided, but a value has not been associated with the key, then it returns undefined.
- If a key was not provided, it returns a hash object containing all key-value pairs.
- Type
- string | object
Example
// The key "Author" is set the value "Mark".
item.setData("Author", "Mark");
// The key "Note" is set the value "This is really important!".
item.setData("Note", "This is really important!");
item.getData("Author"); // returns "Mark"
item.getData(); // returns {"Author":"Mark", "Note":"This is really important!"}
item.getData("FooBar"); // returns undefined
getDataKeys() → {Array.<string>}
Gets an array of data keys known to this object.
Returns:
Returns an array of data keys known to this object. If no data is stored, then an empty array will be returned.
- Type
- Array.<string>
Example
// Returns an empty array before KVPs are stored.
item.getDataKeys(); // returns []
// Returns a list of all keys.
item.setData("Author", "Mark");
item.setData("Note", "This is really important!");
item.getDataKeys(); // returns ["Author", "Note"]
setData(key, value) → {object}
Sets the data value for the given key.
Notes:
- Overwrites any data value already associated with the given key.
- There is no artificial limit imposed on the number of key-value pairs that are stored.
- If limits on the number of KVPs are required, they should be enforced by calling code.
- Setting the value as undefined results in no information for the key being persisted to the server.
- The returned data is not mutated or sanitized, which could lead to a security vulnerability if not sanitized properly before use.
Parameters:
Name | Type | Description |
---|---|---|
key |
string |
The key for which to set the data value. |
value |
string |
This is the value to set for the key.
|
Returns:
The object on which the method was called.
- Type
- object
Example
// Get data returns undefined before the key is set.
item.getData("Author"); // returns undefined
// The key "Author" is set the value "Mark".
item.setData("Author", "Mark");
item.getData("Author"); // returns "Mark"
// The key "Author" is overwritten with the value "Clark".
item.setData("Author", "Clark");
item.getData("Author"); // returns "Clark"
// The key "Author" is unset, by setting the value to undefined.
item.setData("Author", undefined);
item.getData("Author"); // returns undefined
// The value can only be set to a string or undefined.
// All other data types throw.
item.setData("FooBar", null); // throws
item.setData("FooBar", 1); // throws
item.setData("FooBar", true); // throws
item.setData("FooBar", {}); // throws
item.setData("FooBar", []); // throws