Can you explain the HTTP PUT method and its role in server interaction?

The HTTP PUT method is used to create or replace a resource on the server at a specified URL. Its main feature is idempotency, meaning that repeated requests with the same data do not change the result.

When a client sends a PUT request, it transmits a complete representation of the resource that should be saved or updated on the server. If the resource exists, it is replaced; if not, a new one is created.

Example of usage in C# with HttpClient:

var client = new HttpClient();
var content = new StringContent(jsonData, Encoding.UTF8, "application/json");
var response = await client.PutAsync("https://api.example.com/items/1", content);

if (response.IsSuccessStatusCode) {
    Console.WriteLine("Resource successfully updated or created.");
}