ASP.Net application hangs due to string.IndexOf

I had an interesting case recently. We discovered a hang in ASP.Net application caused by string.IndexOf method.Problem description: Frequently, this ASP.Net application would hang and the IIS worker process needs to be restarted for the application to function correctly. This happens even when the load is low. Troubleshooting:Same as before, we captured hang dumps for investigation. From the