contextmenu="supermenu" 属性的应用 右键菜单打开和保存功能

 <div ng-class="{'chat-dialog-news-mine':{{item.isOwn}},'chat-dialog-news-other':{{!item.isOwn}},'chat-dialog-news-file':{{item.content_type == 6}},'chat-dialog-news-mine-file':{{item.isOwn}}&&{{item.content_type == 6}},'chat-dialog-news-other-file':{{!item.isOwn}}&&{{item.content_type == 6}}}" msgId="{{item.imdn_id}}">
                <div contextmenu="supermenu" ng-right-click="decrement_right($event,item)">
                    <i class="icon warn-icon" ng-if="item.isWarn"></i>
                    <i ng-class="{true: 'icon {{item.status}}', false: ''}[{{item.isOwn && item.status !== ''}}]"></i>
                    <i ng-class="{true: 'bubble-icon right-icon', false: 'bubble-icon left-icon'}[{{item.isOwn}}]"></i>
                    <span compile='item.content|trustHtml' ng-click="newsClick($event, item)" ng-dblclick="newsDBClick($event, item)"></span>
                </div>
<!--设置右键弹出样式-->
    <div class="supermenus" id="supermenu" ng-show="iscontextMenus">
        <ul>
            <li ng-click="openRightClick($event)">打开</li>
            <li ng-click="preserveRightClick($event)">保存</li>
        </ul>
    </div>

//点击任意出关闭右键弹窗
        $(document).off('click').on('click', function(e) {
            $scope.iscontextMenus = false;
            if (!$scope.$$phase) {
                $scope.$apply();
            }
        })

//二人会话和群会话消息，右键打开文件功能
        $scope.openRightClick = function ($event) {
            openRightFile ($event);
        }
        function openRightFile ($event) {
            $event.stopPropagation();
            $event.preventDefault();
            $scope.iscontextMenus = false;
            var content_type = items.content_type,//消息的类型是文本消息还是图片消息还是文档消息
                $curTarget = angular.element($event.currentTarget);
            switch (content_type){
                case eucTypes.rcsTypes.ContentType.ContentTypePICTURE:
                    const exec = require('child_process').exec;
                    exec('"' + items.file_path + '"');
                    break;
                case eucTypes.rcsTypes.ContentType.ContentTypeOTHER:
                    if ((messageService.FILE_STATE.RECEIVE_SUCCESS == items.file_state) ||
                        (messageService.FILE_STATE.SEND_SUCCESS == items.file_state)) {
                        const exec = require('child_process').exec;
                        exec('"' +items.file_path + '"');
                    }
                    break;
                default :
                    break;
            }
        };
        //二人会话和群会话消息，右键保存文件功能
        const remote = require('electron').remote;
        var fs = require('fs');
        $scope.preserveRightClick = function($event){
            $event.stopPropagation();
            $event.preventDefault();
            $scope.iscontextMenus = false;
　　　　　　　　electron调用后返回的回调是一个文件的路径；
            const saveFilePath = remote.dialog.showSaveDialog(remote.getCurrentWindow(), {defaultPath:items.file_name}
            );
            var fileReadStream = fs.createReadStream(items.file_path);
            var fileWriteStream = fs.createWriteStream(saveFilePath);
            fileReadStream.pipe(fileWriteStream);
            fileWriteStream.on('close',function(){
                console.log('copy over');
            });

        }

electron框架提供的应用；
const remote = require('electron').remote;
remote.dialog.showSaveDialog(remote.getCurrentWindow(), {defaultPath:"abc.txt"});

node.js fs模块文件的读入和写出
var fs = require('fs');
var fileReadStream = fs.createReadStream('./myjpg.jpg');
var fileWriteStream = fs.createWriteStream('./new_myjpg.jpg');
fileReadStream.pipe(fileWriteStream);
fileWriteStream.on('close',function(){
  console.log('copy over');
}); 

上下文contenxmenu属性的应用；  id="supermenu"