reworked sumseatprices with reduce

client/src/modules/cart.ts

@@ -103,10 +103,13 @@ function appendOption(inSelector: string, inArr: I.TypeBuyerTypeArr): void {
 }
 
 function sumSeatPrices(): string {
-    let overallPrice: number = 0;
+    return config.state.selectedSeatsArr.map(getSeatPrice)
+        .reduce((prev, curr) => prev + curr)
+        .toFixed(2);
+}
 
-    config.state.selectedSeatsArr.forEach(arr => {
-        const seatID: string = arr[0];
+function getSeatPrice(arr: string[]) {
+    const seatID: string = arr[0];
         const buyertypeID: string = arr[1];
         const selectedSeat: I.JSCSelectedSeat = config.state.selectedSeatsObj[seatID];
         const pricescaleID: string = selectedSeat.data.seatsObj.id[0];
@@ -116,9 +119,8 @@ function sumSeatPrices(): string {
             const seatPrice: number | undefined = XMLHelper.getPriceByBuyerTypeID(buyertypeID, pricescaleObj);
 
             if (seatPrice)
-                overallPrice += seatPrice;   
-        } 
-    });
+                return seatPrice;   
+        }
 
-    return overallPrice.toFixed(2);
-}
+        return 0;
+}