在sharepoint javascript模型的每个循环中同步执行QueryAsync

Question

我正在用javascript为sharepoint执行循环。我希望它同步执行，这意味着只有在第一次数据执行完成后，它才应该从第二次开始。如果第一次数据执行完成（无论成功还是失败），那么在每个循环中只有第二次才应该开始。

$.each(selectedSiteCollections, function (index, value) {
                 act.SharePoint.SharePointAppProgress.addStatusRow(act.Resources.StatusInfo.applyFolderNavigation, "applyFolderNavigationId");
                 var siteUrl = value;//_spPageContextInfo.siteServerRelativeUrl + "/" + projectUrl;
                 var  clientContext = act.SharePoint.SharePointAppCommon.getClientContext(siteUrl);
                 var newWebsite = clientContext.get_web();
                 var pageUrl = siteUrl + "/Shared%20Documents/Forms/AllItems.aspx";
                 var homePageUrl = siteUrl + "/Pages/Home.aspx";
                 var jsLinkUrl = '~siteCollection/_catalogs/masterpage/FolderNavigation.js'; //<-- specify JSLink url
                 var page = newWebsite.getFileByServerRelativeUrl(pageUrl);
                 var homePage = newWebsite.getFileByServerRelativeUrl(homePageUrl);

                 var wpm = page.getLimitedWebPartManager(SP.WebParts.PersonalizationScope.shared);
                 var collWebPart = wpm.get_webParts();
                 var wpmHome = homePage.getLimitedWebPartManager(SP.WebParts.PersonalizationScope.shared);
                 var collWebPartHome = wpmHome.get_webParts();
                 clientContext.load(homePage);
                 clientContext.load(collWebPart, 'Include(WebPart.Properties)');
                 clientContext.load(collWebPartHome, 'Include(WebPart.Properties)');
                 clientContext.executeQueryAsync(function () {
                     if (homePage.get_checkOutType() != SP.CheckOutType.online) {
                         homePage.checkOut();
                     }
                     var webPartDef = null;
                     for (var x = 0; x < collWebPart.get_count() && !webPartDef; x++) {
                         var temp = collWebPart.get_item(x);
                         webPartDef = temp;
                     }
                     if (webPartDef != null) {
                         var webpart = webPartDef.get_webPart();

                         var properties = webpart.get_properties();
                         properties.set_item('JSLink', jsLinkUrl);
                         webPartDef.saveWebPartChanges();
                     }

                     var webPartDefHome = null;
                     for (var x = 0; x < collWebPartHome.get_count() && !webPartDefHome; x++) {
                         var temp = collWebPartHome.get_item(x);
                         webPartDefHome = temp;
                     }
                     if (webPartDefHome != null) {
                         var webpart = webPartDefHome.get_webPart();

                         var properties = webpart.get_properties();
                         properties.set_item('JSLink', jsLinkUrl);
                         webPartDefHome.saveWebPartChanges();
                     }

                     homePage.checkIn("ACT Update webpart", SP.CheckinType.majorCheckIn);
                     homePage.publish("ACT Update webpart");
                     clientContext.executeQueryAsync(function () {
                         act.SharePoint.SharePointAppProgress.updateStatusRow(true, "applyFolderNavigationId");
                     }, function (sender, args) { executeAsyncFailed(sender, args, "applyFolderNavigationId"); });
                 }, function (sender, args) { executeAsyncFailed(sender, args, "applyFolderNavigationId"); });
             });

Answer 1

您将无法运行包含异步调用（executeQueryAsync()）的同步foreach循环。任何依赖于异步调用完成的逻辑都需要由异步回调函数触发，这些函数指示函数何时完成执行（以及它是失败还是成功）。

一个可行的方法是创建一个处理单个站点的函数。使用更高范围的变量来跟踪网站集合以及该集合中的当前索引。在executeQueryAsync()调用的onSuccess和onFailure回调中，增加索引并调用函数来处理集合中的下一个站点。

Answer 2

我使用自定义循环逻辑做到了这一点：）

  var loop = function (i) {
                     enableFolderNavigation(selectedSiteCollections[i], i, function () {
                         if (++i < selectedSiteCollections.length) {
                             loop(i);
                         } else {
                             act.SharePoint.SharePointAppProgress.completed(true, "Completed");
                         }
                     });
                 };
                 loop(0);

以及包含异步调用的函数

  enableFolderNavigation = function (item, index, successFolderNavigation) {
           var siteUrl = item.link;//_spPageContextInfo.siteServerRelativeUrl + "/" + projectUrl;
           var title = item.title;
           act.SharePoint.SharePointAppProgress.addStatusRow(act.Resources.StatusInfo.applyFolderNavigation + " :" + title, "applyFolderNavigationId" + index);
           var clientContext = act.SharePoint.SharePointAppCommon.getClientContext(siteUrl);
           var newWebsite = clientContext.get_web();
           var pageUrl = siteUrl + "/Shared%20Documents/Forms/AllItems.aspx";
           var homePageUrl = siteUrl + "/Pages/Home.aspx";
           var jsLinkUrl = '~siteCollection/_catalogs/masterpage/FolderNavigation.js'; //<-- specify JSLink url
           var page = newWebsite.getFileByServerRelativeUrl(pageUrl);
           var homePage = newWebsite.getFileByServerRelativeUrl(homePageUrl);

           var wpm = page.getLimitedWebPartManager(SP.WebParts.PersonalizationScope.shared);
           var collWebPart = wpm.get_webParts();
           var wpmHome = homePage.getLimitedWebPartManager(SP.WebParts.PersonalizationScope.shared);
           var collWebPartHome = wpmHome.get_webParts();
           clientContext.load(homePage);
           clientContext.load(collWebPart, 'Include(WebPart.Properties)');
           clientContext.load(collWebPartHome, 'Include(WebPart.Properties)');
           clientContext.executeQueryAsync(function () {
              // if (homePage.get_checkOutType() != SP.CheckOutType.online) {
                   homePage.checkOut();
              // }
               var webPartDef = null;
               for (var x = 0; x < collWebPart.get_count() && !webPartDef; x++) {
                   var temp = collWebPart.get_item(x);
                   webPartDef = temp;
               }
               if (webPartDef != null) {
                   var webpart = webPartDef.get_webPart();

                   var properties = webpart.get_properties();
                   properties.set_item('JSLink', jsLinkUrl);
                   webPartDef.saveWebPartChanges();
               }

               var webPartDefHome = null;
               for (var x = 0; x < collWebPartHome.get_count() && !webPartDefHome; x++) {
                   var temp = collWebPartHome.get_item(x);
                   webPartDefHome = temp;
               }
               if (webPartDefHome != null) {
                   var webpart = webPartDefHome.get_webPart();

                   var properties = webpart.get_properties();
                   properties.set_item('JSLink', jsLinkUrl);
                   webPartDefHome.saveWebPartChanges();
               }

               homePage.checkIn("ACT Update webpart", SP.CheckinType.majorCheckIn);
               homePage.publish("ACT Update webpart");
               clientContext.executeQueryAsync(function () {
                   act.SharePoint.SharePointAppProgress.updateStatusRow(true, "applyFolderNavigationId" + index);
                   successFolderNavigation();
               }, function (sender, args) { executeAsyncFailed(sender, args, "applyFolderNavigationId" + index); successFolderNavigation(); });
           }, function (sender, args) { executeAsyncFailed(sender, args, "applyFolderNavigationId" + index); successFolderNavigation(); });
       },