Chirag，

Hi Chirag,

根据您的描述，我们可以为SharePoint网站配置基于表单的身份验证，并使用ASP.NET网站中的同一帐户登录SharePoint.

Base on your description, we can configure Forms-Based Authentication for SharePoint site and login SharePoint using the same account in ASP.NET site.

https://blogs.technet.microsoft.com/ptsblog/2013/09/20/configuring-sharepoint-2013-forms-based-authentication-with-sqlmembershipprovider/

或者我们可以在SharePoint中创建服务帐户，然后使用REST API或客户端对象模型(C#)在您的ASP.NET系统中使用此帐户访问SharePoint数据.

Or we can create a service account in SharePoint, then access SharePoint data using this account in your ASP.NET system using REST API or Client Side Object Model(C#).

https://dev .office.com/sharepoint/docs/sp-add-ins/complete-basic-operations-using-sharepoint-client-library-code

***的问候，

丹尼斯