# Subordinate Objects

DS_Item |

The DS_Item subordinate object is used to define an element in a data source. One is defined for each element. The DS_Item object corresponds to a record in the pvxview.itm file.

For information on the pvxview.itm file structure, see Views System File Structures. Properties are read only and are set using corresponding Setxxx( ) methods.

## DS_Item Properties

The following table lists the properties of the DS_Item subordinate object:

Property | Description
Class$ | Class of item.
DataType$ | Data type:
S | String data (Default)
N | Numeric data
Description$ | Item description. This value may be prefaced with an = (equals sign), denoting that the description contains an expression rather than a fixed value beginning at the second character.
Expression$ | Formula/expression to derive the data.
InternalD$ | Internal identifier for the data source element.
Length | Item length ("" null = Default).
Name$ | Field or column name (no trailing "$").
ParentSource | Object identifier for the parent data source object.

## DS_Item Methods

The following table lists the methods of the DS_Item subordinate object:

Method | Description
Description$( ) | Returns the evaluated description.
SetClass(Class$) | Set class of item.
SetType(Type$) | Set data type:
S | String data
N | Numeric data
SetDescription(Description$) | (Internal Use Only) Set item description. Use ViewCtl equivalent.
SetExpression(Expression$) | Set formula/expression to derive the data.
SetInternalID(InternalID) | (Internal Use Only) Set internal identifier for the data source element.
SetLength(Length) | Set item length (0 = Default).
SetName(Name$) | Set field or column name (no trailing "$").