DATAVIEW.FieldByName['fieldname'] : TField
DATAVIEW['fieldname'] : TField
The Field object can be used to retrieve data from a field within a Data View.
Normally the .Value property is used to retrieve the value of a field however you can impose some formatting/conversion by using specific properties like .AsString, and .AsFloat (Refer to See "Referencing Fields" for more information)
Whereas the Value property will retrieve the value as a Variant, the other functions will convert the value to its type. For instance if the field is null then retrieving the value using AsString will result in a blank string being returned instead of a null value.
You can access a field object by referencing it from a Data View object. This is achieved through the FieldByName function however because fields are used so commonly it is normally written in shorthand such as DATAVIEW['FieldName']
Among other things the following tasks can be achieved by working with the Field object
Set or retrieve the value of the field