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How to insert images to a specified index

By default, when you scan or load images, they are appended to the end of the image array in buffer. However, in some business scenarios, the user might want to insert these new images to a specified index. Unfortunately, Dynamic Web TWAIN doesn’t provide a native method for that. The following code snippet shows how it can be done

Insert when acquiring

function acquireToIndex(index) {

    DWObject.IfAppendImage = false;
    DWObject.CurrentImageIndexInBuffer = index;
    DWObject.RegisterEvent('OnPostTransfer', function() {
        DWObject.CurrentImageIndexInBuffer++;
    });
    DWObject.RegisterEvent('OnPostAllTransfers', function() {
        DWObject.IfAppendImage = true;
    });
    DWObject.AcquireImage();

}

Insert when loading

function loadToIndex(index) {

    var oldCount = DWObject.HowManyImagesInBuffer;
    DWObject.RegisterEvent('OnPostLoad', function() {
        var newCount = DWObject.HowManyImagesInBuffer;
        for (var j = 0; j < newCount - oldCount; j++)
            DWObject.MoveImage(oldCount + j, index + j);
    });
    DWObject.LoadImageEx('', 5);

}

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