How to display page number of graphic?

Here is a general-purpose function that will return the Page object of just about any object you pass to it:

function getPage (obj) {
    
    // Gets the page object that contains the object passed in.
    
    var frame = 0, cell = 0;
    var objType = "";
    
    while (obj) {
        
        frame = obj;
        objType = obj.constructor.name;
        
        switch (objType) {
            case "Marker" :
                obj = obj.TextLoc.obj;
                break;
            case "SubCol" :
                obj = obj.ParentTextFrame;
                break;
            case "Tbl" :
                obj = obj.FirstRowInTbl.FirstCellInRow;
                break;
            case "Row" :
                obj = obj.FirstCellInRow;
                break;
            case "Cell" :
            case "Pgf" :
            case "AFrame" :
                obj = obj.InTextFrame;
                break;
            case "TextLine" :
            case "TextFrame" :
            case "UnanchoredFrame" :
            case "Arc" :
            case "Ellipse" :
            case "Group" :
            case "Inset" :
            case "Line" :
            case "Math" :
            case "Polygon" :
            case "Polyline" :
            case "Rectangle" :
            case "RoundRect" :
                if (obj.FrameParent.ObjectValid()) {
                    obj = obj.FrameParent;
                } else {
                    obj = 0;
                }
                break;
            default:
                // Prevent endless loop if unknown object type is found.
                obj = 0;
                break;
        }
    }
    if (frame) {
        return frame.PageFramePage;
    } else {
        return 0;
    }
}