A C# long ID above 2⁵³ can change on its way into Angular.

THE .NET API SENT

1234567890123456789

ANGULAR'S HTTPCLIENT GAVE THE PAGE

1234567890123456800send it back → 404

SENT AS A STRING · [JsonNumberHandling] on the property

"1234567890123456789"send it back → 200

.NET 10 · Angular 22.2 · JSON.parse reads every number as a double, and nothing throws

gdhami.net

A C# long ID above 253 can change on its way into Angular.