Class TDbColSetIter

TDbColSetIter

Support

Supported from 5.0

Description

Provides a useful way to iterate over the contents of a column set.

Defined in TDbColSetIter:
Col(), TDbColSetIter(), operator Tany*(), operator*(), operator++(), operator->()

See also:

• Using TDbColSetIter

TDbColSetIter(const CDbColSet& aColSet);

Description

Constructs a column set iterator over a column set. The iterator now references the first column in the set.

Parameters

const CDbColSet& aColSet The column set to iterate over.

operator TAny*() const;

Description

Tests if the iterator can be dereferenced. This operator is called implicitly when a TDbColSetIter is used in conditional expressions such as:

if (iter)or while (iter)

Return value

TAny* This is NULL if and only if the iterator cannot be dereferenced.

const TDbCol& operator*() const;

Description

Dereferences the iterator on the current column definition.

Return value

TDbCol& A const reference to the current column definition.

const TDbCol* operator->() const;

Description

Gets a member of the currently referenced column definition. This enables the use of the following constructs:

if (iter->iType==EDbColText && iter->iMaxLength<50)

Return value

TDbCol* A const pointer to the current column definition.

TDbColNo Col() const;

Description

Returns a column ordinal in the set for the currently referenced column definition.

Return value

TDbColNo The column ordinal of the current column definition.

TDbColSetIter& operator++();

Description

Moves the iterator to the next column in the set — pre increment operator.

Return value

TDbColSetIter& A reference to this iterator, after the increment operation has been performed.

TDbColSetIter operator++(TInt);

Description

Moves the iterator to the next column in the set — post increment operator.

Note that this is implemented in terms of the pre-increment operator, and is less efficient.

Parameters

TInt Unused: required for the C++ compiler to resolve the ambiguity with the pre-increment operator.

Return value

TDbColSetIter A copy of this iterator, referring to the column definition before the increment operation is performed.