First, you should load the image file to Dynamic Web TWAIN. Currently, we only ensure that images created by Dynamic Web TWAIN or Dynamic TWAIN can be loaded successfully.

You can use the LoadImage method or the LoadImageEx method to load the image file to Dynamic Web TWAIN. Before acquiring images, please check the value of the IfAppendImage property. Set its value to false(the default is true), then the new scanned image will be inserted ahead the current image (you can assign the current image index by CurrentImageIndexInBuffer). Click here to find information about appending new scanned images to an existed multi-page file.

For example, you have a multi-page file including 5 images and you want to insert a new scanned image before the second image.

Code (C#):

//load the image into Dynamic Web TWAIN
private void Load_Click(object sender, EventArgs e)
{
      axDynamicWebTwain1.MaxImagesInBuffer = 8;
      //the maximum number of images can be held in buffer in the trial version is 4
      axDynamicWebTwain1.LoadImage("G:\\wwwroot\\a.tif");
}

//inserte the new scanned image before the current image
private void Add_Click(object sender, EventArgs e)
{
      axDynamicWebTwain1.OpenSource();
      axDynamicWebTwain1.SelectSource();

      axDynamicWebTwain1.IfAppendImage = false;
      //set the value to false, so the new scanned image will be inserted before the current image.
      axDynamicWebTwain1.CurrentImageIndexInBuffer = 1;
      axDynamicWebTwain1.AcquireImage();
}

Reference:

LoadImage  LoadImageEx  IfAppendImage  CurrentImageIndexInBuffer