LTWAINPROPERTYQUERY

typedef struct _LTWAINPROPERTYQUERY
{
   L_UINT uStructSize;
   L_UINT uType;
   union
   {
      pTW_ONEVALUE pltwOneValue;
      pTW_RANGE pltwRange;
      pTW_ENUMERATION pltwEnumeration;
      pTW_ARRAY pltwArray;
   };
} LTWAINPROPERTYQUERY,  * pLTWAINPROPERTYQUERY;

The LTWAINPROPERTYQUERY structure provides information about the capability properties.

Member	Description
uStructSize	Size of the LTWAINPROPERTYQUERY structure, in bytes, for versioning. Use the sizeof() macro to calculate the value.
uType	Holds the type of pointer to use from the union. Possible values are (according to the TWAIN 1.9 specification):
	Value	Meaning
	TWON_ONEVALUE	The container is of type TW_ONEVALUE and only the pltwOneValue pointer is used.
	TWON_RANGE	The container is of type TW_RANGE and only the pltwRange pointer is used.
	TWON_ONEVALUE	The container is of type TW_ENUMERATION and only the pltwEnumeration pointer is used.
	TWON_ONEVALUE	The container is of type TW_ARRAY and only the pltwArray pointer is used.
pltwOneValue	Pointer to a TW_ONEVALUE structure.
pltwRange	Pointer to a TW_RANGE structure.
pltwEnumeration	Pointer to a TW_ENUMERATION structure.
pltwArray	Pointer to a TW_ARRAY structure.

Comments

pLTWAINPROPERTYQUERY is a pointer to a LTWAINPROPERTYQUERY structure. Where the function parameter type is pLTWAINPROPERTYQUERY, you can declare an LTWAINPROPERTYQUERY variable, update the structure's fields, and pass the variable's address in the parameter. Declaring a pLTWAINPROPERTYQUERY variable is necessary only if your program requires a pointer.

LTWAINPROPERTIES is allocated by the LTwain::QueryProperty function and freed by LTwain::FreePropQueryStructure function.