DTWAIN_GetTwainNameFromConstantEx

DTWAIN_GetTwainNameFromConstantExA

DTWAIN_GetTwainNameFromConstantExW

Top  Previous  Next

The DTWAIN_GetTwainNameFromConstantEx function returns the string version of a TWAIN or DTWAIN constant name.

 

LONG DTWAIN_GetTwainNameFromConstantEx (

LONG

ConstantCategory

LONG

ConstantValue

LPTSTR

szBuffer

LONG

Maxlen );

 

Parameters

 

ConstantCategory

The category of TWAIN or DTWAIN constant to search (see DTWAIN TWAIN name constants)

 

ConstantValue

The value of the TWAIN or DTWAIN constant.


szBuffer

Specifies the address of the character buffer to store the string version of the constant name, or NULL


MaxLen

Specifies the maximum number of characters to copy to szBuffer.

 

 

Return Values

If the function succeeds, the number of characters copied to szBuffer is returned.  On function failure, 0 is always returned, and the application can call DTWAIN_GetLastError() for further information.

 

Character specific version

ANSI version:

DTWAIN_GetTwainNameFromConstantExA

Unicode version:

DTWAIN_GetTwainNameFromConstantExW

 

Comments

The DTWAIN_GetTwainNameFromConstantEx function is a utility function that does what DTWAIN_GetTwainNameFromConstant does except for the following differences:


1) If there is no corresponding TWAIN name for the constant ConstantValue, the constant is returned in string form and placed in szBuffer instead of the return code being DTWAIN_FAILURE1.


2) This function will only fail if the DTWAIN DLL has not been initialized with DTWAIN_SysInitialize() or DTWAIN_SysInitializeNoBlocking()

In this case, call DTWAIN_GetLastError() if the return value is 0, to confirm that the failure was due to the DTWAIN DLL not being initialized.


 

TWAIN State Transitions

None.

 

Prerequisite Function Call(s)

DTWAIN_SysInitialize