Who know how to extract all text in an existing .ppt ? Help me?

I need to extract all text in an existing .ppt . Who know how to do ? Help me . Send me your code about this problem . Thanks very much

Hello,

This code example will extract all text from presentation and put it to the “texts” collection.

ArrayList texts = new ArrayList();

for(int i = 0; i < pres.Slides.Count; i++)
{
Slide slide = pres.Slides[ i ];
for(int j = 0; j < slide.Shapes.Count; j++)
{
Shape shape = slide.Shapes[ j ];
if (shape.TextFrame != null)
texts.Add(shape.TextFrame.Text);
}
for(int j = 0; j < slide.Placeholders.Count; j++)
{
Placeholder holder = slide.Placeholders[ j ];
if (holder is TextHolder)
texts.Add(((TextHolder)holder).Text)
}
}