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Gets the specified value from a container.
#include "lttwn.h"
L_LTTWN_API L_INT L_TwainGetNumericContainerBOOLValue(pCapability, nIndex, pbValue)
Pointer to a TW_CAPABILITY structure that references the container value to get.
Index of the value to get. Possible values are:
| Value | Meaning |
|---|---|
| LTWAIN_VALUE_COUNT | [-1] Update pbValue with the number of items in the item list of the specified container. This option is only valid if the container is of type TW_ARRAY or TW_ENUMERATION. If the container is of any other type, this function will return an error code. |
| LTWAIN_VALUE_CURRENT | [-2] Update pbValue with the current value of the container. If the container is of type TW_RANGE, pbValue is updated with the CurrentValue member of the TW_RANGE structure. If the container is of type TW_ENUMERATION, pbValue is updated with the CurrentIndex member of the TW_ENUMERATION structure. If the container is of any other type, the function will return an error code. |
| LTWAIN_VALUE_DEFAULT | [-3] Update pbValue with the default value of the container. If the container is of type TW_RANGE, pbValue is updated with the DefaultValue member of the TW_RANGE structure. If the container is of type TW_ENUMERATION, pbValue is updated with the DefaultIndex member of the TW_ENUMERATION structure. If the container is of any other type, the function will return an error code. |
| LTWAIN_VALUE_MINIMUM | [-4] Update pbValue with the minimum value of the container. If the container is of type TW_RANGE, pbValue is updated with the MinValue member of the TW_RANGE structure. If the container is of any other type, the function will return an error code. |
| LTWAIN_VALUE_MAXIMUM | [-5] Update pbValue with the maximum value of the container. If the container is of type TW_RANGE, pbValue is updated with the MaxValue member of the TW_RANGE structure. If the container is of any other type, the function will return an error code. |
| LTWAIN_VALUE_STEPSIZE | [-6] Update pbValue with the step size of the container. If the container is of type TW_RANGE, pbValue is updated with the StepSize member of the TW_RANGE structure. If the container is of any other type, the function will return an error code. |
| >= 0 | Update pbValue with the value at the specified index. If the container is of type TW_ONEVALUE, nIndex must be zero and pbValue will be updated with the value of the TW_ONEVALUE structure. If the container is of type TW_ARRAY or TW_ENUMERATION, pbValue will be updated with the value at the specified index in the list of items. If the container is of type TW_ENUMERATION or TW_ARRAY, the value must not exceed the number of items in the container's item list or the function will return an error code. |
Reference to a Boolean value to be updated with the specified container value.
| Value | Meaning |
|---|---|
| SUCCESS | The function was successful. |
| ! = SUCCESS | An error occurred. Refer to Return Codes. |
Use this function to get a value from a container's item list when the item list type is Boolean.
L_INT TwainGetNumericContainerBOOLValueExample(L_INT nItemType,HTWAINSESSION hSession){L_INT nRet;TW_CAPABILITY twCap;L_BOOL bValue;nRet = L_TwainStartCapsNeg(hSession);if(nRet != SUCCESS)return nRet;// Fill the TW_CAPABILITY structure with valuestwCap.Cap = CAP_AUTOFEED;twCap.ConType = TWON_ONEVALUE;nRet = L_TwainGetCapability(hSession, &twCap, LTWAIN_CAPABILITY_GETCURRENT);if (nRet != SUCCESS){MessageBox (NULL, TEXT("Failed to get capability"), TEXT("ERROR"), MB_OK);return nRet;}nRet = L_TwainGetNumericContainerItemType(&twCap, &nItemType);if (nRet != SUCCESS){MessageBox (NULL, TEXT("Failed to get capability item type"), TEXT("ERROR"), MB_OK);return nRet;}else if (nItemType == TWTY_BOOL){nRet = L_TwainGetNumericContainerBOOLValue (&twCap, 0, &bValue);if (nRet != SUCCESS){MessageBox (NULL, TEXT("Failed to get capability item value"), TEXT("ERROR"), MB_OK);return nRet;}}nRet = L_TwainEndCapsNeg(hSession);if(nRet != SUCCESS)return nRet;return SUCCESS;}