Set Title for Image in MS Word in order for Spire .NET to identify (locate) the image to replace it with a new one

Question

I want to use Spire .NET to replace an image in a template and save as the output docx file. I use the code below to replace it. My problem is I don't know how to set the image title for the image in MS Word so that Spire knows where my image is to replace.

Document document = new Document("template.docx");
//Loop through the paragraphs of the section
foreach (Paragraph paragraph in document.Sections[0].Paragraphs)
{
    //Loop through the child elements of paragraph
    foreach (DocumentObject docObj in paragraph.ChildObjects)
    {
        if (docObj.DocumentObjectType == DocumentObjectType.Picture)
        {
            DocPicture picture = docObj as DocPicture;
            if (picture.Title == "logo") // <--- I don't know how to set title in Word
            {
                //Replace the image
                picture.LoadImage(Image.FromFile("logo.png"));
            }
        }
    }
}
document.SaveToFile("generated.docx");
document.Close();

Answer 1

Right click on your picture -> Format Picture -> Layout & Properties -> ALT TEXT, then you will find the title part, see below picture (I'm using Office 2013).