我們知道PowerPoint演示文件(PPT)沒有任何方法來識別幻燈片內的特定形狀，除非使用一個內部獨特的Id。但是這種方法對于開發者來說優勢相當復雜的。本文將描述一個簡單的技術就能更容易的在幻燈片中找到一個特定的形狀，而不使用它的內部Id。

在這里我們需要借助Aspose.Slides這個控件的幫助。

所有添加到幻燈片的形狀都有一些Alternative Text替代文本。我們建議開發人員使用Alternative Text替代文本尋找一個特定的形狀。您可以使用MS PowerPoint來定義替代文本的對象,如下所示:

具體實現代碼如下：

[C#]

//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;
}

[Visual Basic]

'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).AlternativeText.CompareTo(alttext) = 0 Then
            Return slide.Shapes(i)
        End If
    Next

    Return Nothing
End Function

[C#]

//Calling FindShape method and passing the slide reference with the
//alternative text of the shape to be found
Shape shape = FindShape(slide, "Shape1");

[Visual Basic]

'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")