DTWAIN_ArrayGetAtWideString
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The DTWAIN_ArrayGetAtWideString function retrieves a wide string value from a DTWAIN_ARRAY.
DTWAIN_BOOL DTWAIN_ArrayGetAtWideString (
Parameters Array DTWAIN_ARRAY that the value will be retrieved from.
Position Index of value to retrieve.
pValue Pointer to the wide character buffer that will receive the string. The returned string is terminated with a NULL value.
Return Values If the function succeeds, TRUE is returned. If the function fails FALSE is returned.
Comments DTWAIN_ArrayGetAtWideString is a specialized version of DTWAIN_ArrayGetAt.
The DTWAIN_ArrayGetAtWideString function copies the string located at index Index to the address pValue. A DTWAIN_ARRAY is indexed starting from position 0 through position n-1, where n is the total number of items in the DTWAIN_ARRAY Array.
Note that pValue must point to a character buffer that has a length greater or equal to the length of the string that is retrieved, with also room for the terminating null character.. To ensure that the buffer is sized correctly, call DTWAIN_ArrayGetStringLength to get the number of characters:
Below is a small C++ code example of ensuring that strings are retrieved correctly from a buffer:
DTWAIN_ARRAY sArray; // create the array sArray = DTWAIN_ArrayCreate( DTWAIN_ARRAYWIDESTRING, 1);
// set a string at the first element DTWAIN_ArraySetAtWideString( sArray, 0, L"This is a wide string");
// get the length of the string LONG sLen = DTWAIN_ArrayGetStringLength( sArray, 0 );
// create a dynamic string using new[]. Make sure we have room for the NULL terminator */ LPWSTR pBuffer = new WCHAR[ sLen + 1 ];
// get the string DTWAIN_ArrayGetAtWideString( sArray, 0, pBuffer );
Other languages should also make the appropriate provisions provided by the language to ensure that the buffer passed to DTWAIN_ArrayGetAtWideString is large enough to hold the string, plus the ending null terminator. If this is not done, the application may crash or experience erratic behavior.
This function will only work for DTWAIN_ARRAY's that can store wide string values (i.e. the DTWAIN_ARRAY was created with the DTWAIN_ARRAYWIDESTRING style. See DTWAIN_ArrayCreate for more information).
TWAIN State Transitions None.
Prerequisite Function Call(s)
See Also |