This interface is simply a wrapper interface for nsISupportsString so the preferences service can have a unique identifier to distinguish between requests for normal wide strings 
nsISupportsString) and 'localized' wide strings, which get their default values from properites files. 
 
 
Inherits from: 
 
nsISupports 
Last changed in Gecko 1.8 (Firefox 1.5 / Thunderbird 1.5 / SeaMonkey 1.0)Method overview
| void setDataWithLength(in unsigned long length, [size_is(length)] in wstring data); | 
| wstring toString(); | 
Attributes
| Attribute | Type | Description | 
| data | wstring | Provides access to string data stored in this property. | 
Methods
setDataWithLength()
Used to set the contents of this object.
void setDataWithLength( in unsigned long length, [size_is(length)] in wstring data );
Parameters
- 
  length
- 
  The length of the string. This value should not include space for the nullterminator, nor should it account for the size of a character. It should only be the number of characters for which there is space in the string.
- 
  data
- The string data to be stored.
toString()
Used to retrieve the contents of this object into a wide string.
Note: This makes a copy of the string argument passed in.
wstring toString();
Parameters
None.
Return value
Returns wstring - The string containing the data stored within this object.