String.IndexOf("\0") returns always 0 in .NET 5.0

[ghost]

Here's a small example code to reproduce the issue:

byte[] buf = { (byte)'A', (byte)'B', (byte)'C', (byte)'\0' };
string s = Encoding.ASCII.GetString(buf);
Console.WriteLine(s.IndexOf("\0")); /* outputs 0 for .NET 5 and 3 for .NET Core 3.1 */
Console.WriteLine(s.IndexOf('\0')); /* outputs 3 for .NET 5 and 3 for .NET Core 3.1 */

Ok, it doesn't make much sense to search for "\0" instead of '\0', but the results differ from .NET Core 3.1.

[ghost]

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Issue Details

---

Here's a small example code to reproduce the issue:

byte[] buf = { (byte)'A', (byte)'B', (byte)'C', (byte)'\0' };
string s = Encoding.ASCII.GetString(buf);
Console.WriteLine(s.IndexOf("\0")); /* outputs 0 for .NET 5 and 3 for .NET Core 3.1 */
Console.WriteLine(s.IndexOf('\0')); /* outputs 3 for .NET 5 and 3 for .NET Core 3.1 */

Ok, it doesn't make much sense to search for "\0" instead of '\0', but the results differ from .NET Core 3.1.

Author:	fn2020
Assignees:	-
Labels:	area-System.Globalization, untriaged
Milestone:	-

[huoyaoyuan]

duplicate of #46569

[ghost]

Looks like this is correct for .NET 5:

https://docs.microsoft.com/en-us/dotnet/standard/base-types/string-comparison-net-5-plus