Resolved platform mapping form save error (#189)

gaseous-server/wwwroot/pages/dialogs/platformmapedit.html

@@ -144,6 +144,7 @@
 
             // start populating drop downs
             if (result.webEmulator) {
+                if (result.webEmulator.availableWebEmulators) {
                     if (result.webEmulator.availableWebEmulators.length > 0) {
                         availableWebEmulators = result.webEmulator.availableWebEmulators;
 
@@ -181,6 +182,10 @@
                     // no emulators available
                     DisplayWebEmulatorContent(false);
                 }
+            } else {
+                // no emulators available
+                DisplayWebEmulatorContent(false);
+            }
 
             var biosTableHeaders = [
                         {
@@ -269,11 +274,7 @@
     }
 
     function SubmitMappingItem() {
-        var alternateNames = [];
-        for (var i = 0; i < document.getElementById('mapping_edit_alternativenames').childNodes.length; i++) {
-            var optionObj = document.getElementById('mapping_edit_alternativenames').childNodes[i];
-            alternateNames.push(optionObj.innerHTML);
-        }
+        var alternateNames = $('#mapping_edit_alternativenames').val();
 
         var knownExtensions = $('#mapping_edit_supportedfileextensions').val();
         
@@ -293,6 +294,7 @@
 
         var bios = [];
         var biosTable = document.getElementById('EditableTable_bios');
+        if (biosTable) {
             // get rows
             for (var i = 0; i < biosTable.childNodes.length; i++) {
                 var rowObj = biosTable.childNodes[i];
@@ -323,6 +325,7 @@
                     bios.push(biosObj);
                 }
             }
+        }
 
         var item = {
             "igdbId": Number(modalVariables),