首页 > 解决方案 > 通过 AJAX 请求访问 SharePoint-API 时如何解决 CORS 问题?

问题描述

我为客户设置了 Dynamics-Portal。客户希望在门户上显示来自 SharePoint 的图像。

我的想法是使用带有 Ajax 的 jQuery 来访问 SharePoint-API。

由于我的网络编程经验相当有限,我需要帮助来理解我遇到的错误。

经过一番阅读,这是我的第一次尝试:

$.ajax({
          url: "https://example.SharePoint.com/_api/web/GetFolderByServerRelativeUrl('/ImageFolder')/Files",
          type: 'GET',
          Accept: "application/json;odata=verbose",
          crossDomain: true,
          contentType: 'application/json;odata=verbose',
          dataType: 'json',
          xhrFields: { withCredentials: true }
        })

这会产生以下错误:

Access to XMLHttpRequest at 'https://example.SharePoint.com/_api/web/GetFolderByServerRelativeUrl('/ImageFolder')/Files'
    from origin 'https://myDynamicsPortal.com' has been blocked by CORS policy:
    Response to preflight request doesn't pass access control check:
    The value of the 'Access-Control-Allow-Origin' header in the response must not be the wildcard '*' when the request's credentials mode is 'include'.
    The credentials mode of requests initiated by the XMLHttpRequest is controlled by the withCredentials attribute.

现在我通过添加“?callback =?”来更改上面的Ajax。到网址。像这样:

url:"https://example.SharePoint.com/_api/web/.../Files?callback=?"

这似乎与更改相同:

dataType: 'json'
to
dataType: 'jsonp'

错误消失了,但出现了这个警告:

Cross-Origin Read Blocking (CORB) blocked cross-origin response
https://example.SharePoint.com/_api/web/GetFolderByServerRelativeUrl('/ImageFolder')/Files?callback=jQuery13423412342134134_1234123412341234&_=12341341234 
with MIME type application/atom+xml.

See https://www.chromestatus.com/feature/5629709824032768 for more details.

状态码是 200 但错误:"JQuery13423412342134134_1234123412341234 was not called"出现。

我从这些错误、警告和我的研究中理解/解释的是:

一旦需要凭据,服务器就不能再将通配符用于允许的来源。由于我无法更改 SharePoints 源策略,因此我寻找其他方法来解决该问题。

似乎服务器不明白我期望回调,因为我没有配置“jsonp”或“?callback =?”。这样做后,错误消失了,但似乎由于 CORB(跨源读取阻止),我的门户将不接受响应。

为什么 SharePoint 突然接受我的请求?(或者是吗?)

为什么我会获得 http 200 成功 - 但是这个错误:

"JQuery13423412342134134_1234123412341234 was not called"

连同解析错误?

提前致谢并致以最诚挚的问候

杰克

标签: jqueryajaxsharepointcorsdynamics-365

解决方案


尝试添加代码(support.cors):

$.support.cors = true;

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