What is the proper way to declare a Microsoft class to use in my code.

Question

What is the proper way to declare a Microsoft class to use in my code. The quick and dirty way I am doing it here, I know, is not correct

Microsoft SharePoint.Client.List newList = null;

I think it is something like this

Microsoft.SharePoint.Client.List newList = new Microsoft.SharePoint.Client.List();

Answer 1

Your terminology is a little confusing. If you want to create an instance of a type/class that is defined by somebody else then it is something like this.

Microsoft.SharePoint.Client.List newList = new Microsoft.SharePoint.Client.List();

//Or the shorter version
var newList = new Microsoft.SharePoint.Client.List();

The warning you're getting is because you're trying to assign null to a variable that is not typed as supporting null. That means you're building newer (e.g. NET 6+) code and you have enabled nullable reference types (the default).

Answer 2

Hi @William Thompson ,

The List class in the Microsoft.SharePoint.Client namespace cannot be instantiated directly using the new keyword. Instead, you should use the ListCreationInformation class to create a new list.

using Microsoft.SharePoint.Client;

// Assuming you have a ClientContext object named clientContext
ClientContext clientContext = new ClientContext("http://YourSharePointSiteUrl");

ListCreationInformation creationInfo = new ListCreationInformation();
creationInfo.Title = "New List Title";
creationInfo.TemplateType = (int)ListTemplateType.GenericList;

List newList = clientContext.Web.Lists.Add(creationInfo);
clientContext.ExecuteQuery();

Best Regards.

Jiachen Li

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