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Represents a variant data type for the MFC ODBC classes.
class CDBVariant
Members
Public Constructors
Name |
Description |
|---|---|
Constructs a CDBVariant object. |
Public Methods
Name |
Description |
|---|---|
Clears the CDBVariant object. |
Public Data Members
Name |
Description |
|---|---|
Contains the data type of the currently stored value. Type DWORD. |
Public Union Members
Name |
Description |
|---|---|
Contains a value of type BOOL. |
|
Contains a value of type unsigned char. |
|
Contains a value of type double. |
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Contains a value of type float. |
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Contains a value of type short. |
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Contains a value of type long. |
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Contains a pointer to an object of type CLongBinary. |
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Contains a pointer to an object of type TIMESTAMP_STRUCT. |
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Contains a pointer to an object of type CString. |
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Stores a pointer to an ASCII CString object. |
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Stores a pointer to a wide CString object. |
Remarks
CDBVariant does not have a base class.
CDBVariant is similar to COleVariant; however, CDBVariant does not use OLE. CDBVariant allows you to store a value without worrying about the value's data type. CDBVariant tracks the data type of the current value, which is stored in a union.
Class CRecordset utilizes CDBVariant objects in three member functions: GetFieldValue, GetBookmark, and SetBookmark. For example, GetFieldValue allows you to dynamically fetch data in a column. Because the data type of the column may not be known at run time, GetFieldValue uses a CDBVariant object to store the column's data.
Inheritance Hierarchy
CDBVariant
Requirements
Header: afxdb.h