SPFieldUserValue : Value does not fall within the expected range

Question

Following piece of code returning following error not sure where is the problem,

Exception Details: System.ArgumentException: Value does not fall within the expected range.

public static SPUser convertStringToSPUser(string struser)
{
    SPFieldUserValue userValue = new SPFieldUserValue(SPContext.Current.Web, struser);
    SPUser objSPUser = userValue.User;
    return objSPUser;
}

My string is something like, "S, Rishi".

Answer 1

In order to create an instance of SPFieldUserValue you should Pass a string with the following format: [int];#[domain]\[username]

The easiest way to get that value from a list item is: ListItem[field_GUID].ToString();