System.ArgumentOutOfRangeException on ".ToString()" of SqlException

[BoBiene]

Describe the bug

Unable to call ".ToString()" on SqlException

Exception message:
System.ArgumentOutOfRangeException: "Der Index lag außerhalb des Bereichs. Er darf nicht negativ und kleiner als die Sammlung sein.
Parametername: index"

Stack trace:
 	mscorlib.dll!System.Collections.ArrayList.this[int].get(int index)	Unbekannt
	Microsoft.Data.SqlClient.dll!Microsoft.Data.SqlClient.SqlException.Number.get()	Unbekannt
 	Microsoft.Data.SqlClient.dll!Microsoft.Data.SqlClient.SqlException.ToString()	Unbekannt
 	mscorlib.dll!System.Text.StringBuilder.AppendFormatHelper(System.IFormatProvider provider, string format, System.ParamsArray args)	Unbekannt
 	mscorlib.dll!string.FormatHelper(System.IFormatProvider provider, string format, System.ParamsArray args)	Unbekannt
 	mscorlib.dll!string.Format(string format, object[] args)	Unbekannt

[JRahnama]

@BoBiene , Thanks for bringing this to our attention. Can you kindly provide us a sample code resulting in this issue that we can start looking into it?

[cheenamalhotra]

@BoBiene

Just to add context from what I observe, your error message is "The index was out of range. It must not be negative and smaller than the collection." which seems to occur when this is called: https://github.com/dotnet/SqlClient/blob/master/src/Microsoft.Data.SqlClient/netfx/src/Microsoft/Data/SqlClient/SqlException.cs#L114 and does your application targets .NET Framework? Kindly confirm.

        public int Number
        {
            get { return this.Errors[0].Number; }
        }

As I see in .NET Core this is handled: https://github.com/dotnet/SqlClient/blob/master/src/Microsoft.Data.SqlClient/netcore/src/Microsoft/Data/SqlClient/SqlException.cs#L104

        public int Number
        {
            get { return Errors.Count > 0 ? Errors[0].Number : default; }
        }

Never-the-less I think this should be fixed, along with other places where null checks are missing. cc @JRahnama

[BoBiene]

Hi @cheenamalhotra,

i can confirm that this issue is only when I target .NET 472, with .NET Core 3.1 it is working.