Struct array as a Web Property

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Complex web properties, such as structs and/or arrays, have been supported since DataFlex 18.1.

The documentation on this however is extremely thin. It doesn't exist at the time of writing this, so you are left on your own on how-to figure out how that works.

The usage of a struct requires that you serialize/deserialize the data against a matching javascript object, just like when you pass a parameter. Perhaps there's a better way, but I am not aware of that.

What follows is a simple code example taken from the syncfusion library, to give you an idea on how this works.

On the DataFlex side:

Struct tCarouselItem
  String sImage
  String sAltText
  String sCaption

... snip ....

    Procedure Construct_Object
        Forward Send Construct_Object
        { WebProperty=Client }
        Property tCarouselItem[]  pCarouselItems

... snip ....

    Procedure LoadImages
        tCarouselItem   CarouselItem
        tCarouselItem[] CarouselItems
        ... some code filling the array and putting that in array variable CarouselItems
        Send LoadData sData
        WebSet pCarouselItems to CarouselItems

So we can use a WebSet to transfer the data, just like with other properties.

On the javascript side:

// carousel data.
tActionCarouselItemFormat = {
        image : df.tString,
        altText : df.tString,
        caption : df.tString


sf.WebCarousel = function WebCarousel(sName, oParent) {
    // Forward send constructor, sName, oParent);

    // Properties:
... snip ....
    this.prop(df.tString,"psSyncfusionLicense", "");
    this.prop(df.tAdv,"pCarouselItems", "");
..snip ...

    carouselItemsChanged : function() {
        let carousel=this._osfWebCarousel;
        let tData=null;
        let tItems=null;
            tData = this.pCarouselItems;
            tItems = df.sys.vt.deserialize(tData, [tActionCarouselItemFormat] );

On the javascript end after getting the advanced client property into a variable, you only have to deserialize it to get at the data.