Templates > VpeSetTplFieldToNull

Assigns a null-value to a field. A field has a null-value after calling VpeClearTplFields or after explicitly assigning a null-value to a Field by either calling VpeSetFieldToNull or by calling this function.

int VpeSetTplFieldToNull(

VpeHandle hTemplate,

LPCSTR data_source_prefix,

LPCSTR field_name

)

VpeHandle hTemplate

Template Handle

LPCSTR data_source_prefix

prefix of the Data Source, this is the unique name of a Data Source as defined in dycodoc

LPCSTR field_name

name of the Data Source Field

Returns:

Value	Description
True	the null-value was assigned successfully to the field
False	the null-value was not assigned successfully to the field

Remarks:

A null-value is a special value, like in SQL databases. An empty string or an integer / double / date with the value zero are not null-values.

In string expressions a null-value is treated like an empty string. In numeric or date expressions, a null-value is treated like a zero.

The Template Object itself offers simple methods to access a Field's value directly, i.e. without retrieving a Field Object first. See VpeSetTplFieldToNull.