UnityEditor.EditorUtility.SaveBuildPanel C# (CSharp) Method

        internal static extern string SaveBuildPanel(BuildTarget target, string title, string directory, string defaultName, string extension, out bool updateExistingBuild);
        /// <summary>

            private static bool PickBuildLocation(BuildTargetGroup targetGroup, BuildTarget target, BuildOptions options, out bool updateExistingBuild)
            {
                updateExistingBuild = false;
                var previousPath = EditorUserBuildSettings.GetBuildLocation(target);

                string defaultFolder;
                string defaultName;

                if (previousPath == String.Empty)
                {
                    defaultFolder = FileUtil.DeleteLastPathNameComponent(Application.dataPath);
                    defaultName   = "";
                }
                else
                {
                    defaultFolder = FileUtil.DeleteLastPathNameComponent(previousPath);
                    defaultName   = FileUtil.GetLastPathNameComponent(previousPath);
                }

                string extension = PostprocessBuildPlayer.GetExtensionForBuildTarget(targetGroup, target, options);

                // Invalidate default name, if extension mismatches the default file (for ex., when switching between folder type export to file type export, see Android)
                if (extension != Path.GetExtension(defaultName).Replace(".", ""))
                {
                    defaultName = string.Empty;
                }

                // Hack: For Windows Standalone, we want the BuildPanel to choose a folder,
                // but we don't want BuildPlayer to take a folder path because historically it took an .exe path
                // and we would be breaking tons of projects!
                bool   isWindowsStandalone = target == BuildTarget.StandaloneWindows || target == BuildTarget.StandaloneWindows64;
                string realExtension       = extension;

                if (isWindowsStandalone)
                {
                    extension = string.Empty;
                    // Remove the filename.exe part from the path
                    if (!string.IsNullOrEmpty(defaultName))
                    {
                        defaultName = Path.GetDirectoryName(defaultName);
                    }
                }

                string title = "Build " + BuildPlatforms.instance.GetBuildTargetDisplayName(targetGroup, target);
                string path  = EditorUtility.SaveBuildPanel(target, title, defaultFolder, defaultName, extension, out updateExistingBuild);

                if (path == string.Empty)
                {
                    return(false);
                }

                if (isWindowsStandalone)
                {
                    extension = realExtension;
                    path      = Path.Combine(path, Paths.MakeValidFileName(PlayerSettings.productName) + '.' + extension);
                }

                if (!IsBuildPathValid(path))
                {
                    return(false);
                }

                // Enforce extension if needed
                if (extension != string.Empty && FileUtil.GetPathExtension(path).ToLower() != extension)
                {
                    path += '.' + extension;
                }

                // A path may not be empty initially, but it could contain, e.g., a drive letter (as in Windows),
                // so even appending an extension will work fine, but in reality the name will be, for example,
                // G:/
                //Debug.Log(path);

                string currentlyChosenName = FileUtil.GetLastPathNameComponent(path);

                if (currentlyChosenName == string.Empty)
                {
                    return(false); // No nameless projects, please
                }
                // We don't want to re-create a directory that already exists, this may
                // result in access-denials that will make users unhappy.
                string check_dir = extension != string.Empty ? FileUtil.DeleteLastPathNameComponent(path) : path;

                if (!Directory.Exists(check_dir))
                {
                    Directory.CreateDirectory(check_dir);
                }

                // On OSX we've got replace/update dialog, for other platforms warn about deleting
                // files in target folder.
                if ((target == BuildTarget.iOS) && (Application.platform != RuntimePlatform.OSXEditor))
                {
                    if (!FolderIsEmpty(path) && !UserWantsToDeleteFiles(path))
                    {
                        return(false);
                    }
                }

                EditorUserBuildSettings.SetBuildLocation(target, path);
                return(true);
            }