Dynamics 365 filter sub grid lookup on add - D365 On-premise lookup filter on subgrid using Java script

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// START

// JScript source code

function setSubgridLookupFiltering() {

    var subgridAddButtonId = "Requirements_addImageButton";

    //Try to get the element from both the current and the parent document.

    var subgridAddButton = document.getElementById(subgridAddButtonId) || window.parent.document.getElementById(subgridAddButtonId);

    //This script may run before the subgrid has been fully loaded on the form. If this is the case,

    //delay and retry until the subgrid has been loaded.

    if (subgridAddButton == null) {

        setTimeout(setSubgridLookupFiltering, 2000);

        return;

    }

    //Local function to retrieve the lookup control and apply the filter. We will queue this function in the click event handler of the

    //Add button's click event.

    var getSubgridLookupAndAddFilter = function () {

        debugger;

        var subgridLookup = Xrm.Page.getControl("lookup_Requirements");

        //Delay and retry until we can locate the lookup.

        if (subgridLookup == null) {

            setTimeout(getSubgridLookupAndAddFilter, 200);

            return;

        }

        //This is a custom property we are tagging on to the lookup control to ensure that we will

        //apply the custom filter only once when the Add button is first clicked.

        if (subgridLookup.customFilterAdded) {

            return;

        }

        subgridLookup.addPreSearch(function () {

            debugger;

            //Standard logic to build up the filter query string

            var filterQuery = "";

            // var Property = Xrm.Page.getAttribute("").getValue();

            var lookupfield = new Array;

            lookupfield = Xrm.Page.getAttribute("msdyn_account").getValue();//lookup name which lookup values need to be filters where sub grid is placed

            if (lookupfield != null) {

                var lookupid = lookupfield[0].id;

            }

            filterQuery = "<filter  type='and'><condition attribute='has_property' operator='eq' value='" + lookupid + "'/></filter>";

            //Standard call to add filter to the lookup control

            subgridLookup.addCustomFilter(filterQuery, "has_pointmapping");//subgrid entity schema name

        });

        //Mark the fact that we have already added the filter so that we won't do it again the next time the user clicks the Add button.

        subgridLookup.customFilterAdded = true;

    };

    //Attach the function to retrieve the lookup and apply the filter to the Add button's click event. Remember that we

    //can only get the lookup after the user has clicked the Add button.

    subgridAddButton.addEventListener("click", function () {

        debugger;

        setTimeout(getSubgridLookupAndAddFilter, 200);

    });

}

//END

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