SPFieldMultiLineText Class
Represents a text field that can contain multiple lines.
Namespace:
Microsoft.SharePoint
Assembly: Microsoft.SharePoint (in Microsoft.SharePoint.dll)
Available in Sandboxed Solutions: Yes
Available in SharePoint Online
If you set properties of the SPFieldMultiLineText class, you must call the Update method for changes to take effect in the database.
The SPFieldMultiLineText class corresponds to the Note data type that is specified through the Type attribute of the Field element.
Notes to Inheritors
In SharePoint Foundation, columns based on custom field types are read-only in Datasheet view.