SP.WebCreationInformation.language property (sp.js)
Gets or sets the locale ID that specifies the language of the new site.
Applies to: apps for SharePoint | SharePoint Foundation 2013 | SharePoint Server 2013
var value = SP.WebCreationInformation.get_language ()
var value = SP.WebCreationInformation.set_language ()
Return value
Type: Number
Remarks
It must be a valid LCID. An LCID is a 4-byte value. The value supplied in an LCID is a standard numeric substitution for the international [RFC4646] string.