 | It is important to know that PowerPoint Presentation files (PPT) do not have any way to identify shapes on a slide except an internal unique Id. It seems to be difficult for developers to find a shape using its internal unique Id. This topic will describe a simple technique to make it easier to find a specific shape on a slide without using its internal Id. |
Finding a Shape on a Slide
All shapes added to the slides have some Alternative Text . We suggest developers to use alternative text for finding a specific shape. You can use MS PowerPoint to define the alternative text for objects which you are planning to change in the future as shown below:
All shapes added to the slides have some Alternative Text . We suggest developers to use alternative text for finding a specific shape. You can use MS PowerPoint to define the alternative text for objects which you are planning to change in the future as shown below:
Figure : Setting alternative text of a shape using MS PowerPoint
After setting the alternative text of any desired shape, you can then open that presentation using Aspose.Slides for .NET and iterate through all shapes added to a slide. During each iteration, you can check the alternative text of the shape and the shape with the matching alternative text would be the shape required by you.
To demonstrate this technique in a better way, we have created a method, FindShape that does the trick to find a specific shape in a slide and then simply returns that shape.
Example
//Method implementation to find a shape in a slide using its alternative text Shape FindShape(Slide slide, string alttext) { //Iterating through all shapes inside the slide for (int i = 0; i < slide.Shapes.Count; i++) { //If the alternative text of the slide matches with the required one then //return the shape if (slide.Shapes[i].AlternativeText.CompareTo(alttext) == 0) return slide.Shapes[i]; } return null; }
'Method implementation to find a shape in a slide using its alternative text Private Function FindShape(ByVal slide As Slide, ByVal alttext As String) As Shape Dim i As Integer 'Iterating through all shapes inside the slide For i = 0 To slide.Shapes.Count - 1 'If the alternative text of the slide matches with the required one 'then return the shape If slide.Shapes(i).AlternativeTextCompareTo(alttext) = 0 Then Return slide.Shapes(i) End If Next Return Nothing End Function
//Calling FindShape method and passing the slide reference with the //alternative text of the shape to be found Shape shape = FindShape(slide, "Shape1");
'Calling FindShape method and passing the slide reference with the
'alternative text of the shape to be found
Dim shape As Shape = FindShape(Slide, "Shape1")