Const vs static .cs

using System;
public class C {
    
    const string test = "stuff";
    private static string test2 = "stuff2";
    
    public static void M() {
        System.Console.WriteLine(test);
        System.Console.WriteLine(test2);
    }
}

​Const vs static .il

.assembly _
{
    .custom instance void [System.Runtime]System.Runtime.CompilerServices.CompilationRelaxationsAttribute::.ctor(int32) = (
        01 00 08 00 00 00 00 00
    )
    .custom instance void [System.Runtime]System.Runtime.CompilerServices.RuntimeCompatibilityAttribute::.ctor() = (
        01 00 01 00 54 02 16 57 72 61 70 4e 6f 6e 45 78
        63 65 70 74 69 6f 6e 54 68 72 6f 77 73 01
    )
    .custom instance void [System.Runtime]System.Diagnostics.DebuggableAttribute::.ctor(valuetype [System.Runtime]System.Diagnostics.DebuggableAttribute/DebuggingModes) = (
        01 00 07 01 00 00 00 00
    )
    .permissionset reqmin = (
        2e 01 80 8a 53 79 73 74 65 6d 2e 53 65 63 75 72
        69 74 79 2e 50 65 72 6d 69 73 73 69 6f 6e 73 2e
        53 65 63 75 72 69 74 79 50 65 72 6d 69 73 73 69
        6f 6e 41 74 74 72 69 62 75 74 65 2c 20 53 79 73
        74 65 6d 2e 52 75 6e 74 69 6d 65 2c 20 56 65 72
        73 69 6f 6e 3d 37 2e 30 2e 30 2e 30 2c 20 43 75
        6c 74 75 72 65 3d 6e 65 75 74 72 61 6c 2c 20 50
        75 62 6c 69 63 4b 65 79 54 6f 6b 65 6e 3d 62 30
        33 66 35 66 37 66 31 31 64 35 30 61 33 61 15 01
        54 02 10 53 6b 69 70 56 65 72 69 66 69 63 61 74
        69 6f 6e 01
    )
    .hash algorithm 0x00008004 // SHA1
    .ver 0:0:0:0
}

.class private auto ansi '<Module>'
{
} // end of class <Module>

.class public auto ansi beforefieldinit C
    extends [System.Runtime]System.Object
{
    .custom instance void System.Runtime.CompilerServices.NullableContextAttribute::.ctor(uint8) = (
        01 00 01 00 00
    )
    .custom instance void System.Runtime.CompilerServices.NullableAttribute::.ctor(uint8) = (
        01 00 00 00 00
    )
    // Fields
    .field private static literal string test = "stuff"
    .field private static string test2

    // Methods
    .method public hidebysig static 
        void M () cil managed 
    {
        // Method begins at RVA 0x20a2
        // Code size 24 (0x18)
        .maxstack 8

        IL_0000: nop
        IL_0001: ldstr "stuff"
        IL_0006: call void [System.Console]System.Console::WriteLine(string)
        IL_000b: nop
        IL_000c: ldsfld string C::test2
        IL_0011: call void [System.Console]System.Console::WriteLine(string)
        IL_0016: nop
        IL_0017: ret
    } // end of method C::M

    .method public hidebysig specialname rtspecialname 
        instance void .ctor () cil managed 
    {
        // Method begins at RVA 0x20bb
        // Code size 8 (0x8)
        .maxstack 8

        IL_0000: ldarg.0
        IL_0001: call instance void [System.Runtime]System.Object::.ctor()
        IL_0006: nop
        IL_0007: ret
    } // end of method C::.ctor

    .method private hidebysig specialname rtspecialname static 
        void .cctor () cil managed 
    {
        // Method begins at RVA 0x20c4
        // Code size 11 (0xb)
        .maxstack 8

        IL_0000: ldstr "stuff2"
        IL_0005: stsfld string C::test2
        IL_000a: ret
    } // end of method C::.cctor

} // end of class C

.class private auto ansi sealed beforefieldinit Microsoft.CodeAnalysis.EmbeddedAttribute
    extends [System.Runtime]System.Attribute
{
    .custom instance void [System.Runtime]System.Runtime.CompilerServices.CompilerGeneratedAttribute::.ctor() = (
        01 00 00 00
    )
    .custom instance void Microsoft.CodeAnalysis.EmbeddedAttribute::.ctor() = (
        01 00 00 00
    )
    // Methods
    .method public hidebysig specialname rtspecialname 
        instance void .ctor () cil managed 
    {
        // Method begins at RVA 0x2050
        // Code size 8 (0x8)
        .maxstack 8

        IL_0000: ldarg.0
        IL_0001: call instance void [System.Runtime]System.Attribute::.ctor()
        IL_0006: nop
        IL_0007: ret
    } // end of method EmbeddedAttribute::.ctor

} // end of class Microsoft.CodeAnalysis.EmbeddedAttribute

.class private auto ansi sealed beforefieldinit System.Runtime.CompilerServices.NullableAttribute
    extends [System.Runtime]System.Attribute
{
    .custom instance void [System.Runtime]System.Runtime.CompilerServices.CompilerGeneratedAttribute::.ctor() = (
        01 00 00 00
    )
    .custom instance void Microsoft.CodeAnalysis.EmbeddedAttribute::.ctor() = (
        01 00 00 00
    )
    .custom instance void [System.Runtime]System.AttributeUsageAttribute::.ctor(valuetype [System.Runtime]System.AttributeTargets) = (
        01 00 84 6b 00 00 02 00 54 02 0d 41 6c 6c 6f 77
        4d 75 6c 74 69 70 6c 65 00 54 02 09 49 6e 68 65
        72 69 74 65 64 00
    )
    // Fields
    .field public initonly uint8[] NullableFlags

    // Methods
    .method public hidebysig specialname rtspecialname 
        instance void .ctor (
            uint8 ''
        ) cil managed 
    {
        // Method begins at RVA 0x2059
        // Code size 24 (0x18)
        .maxstack 8

        IL_0000: ldarg.0
        IL_0001: call instance void [System.Runtime]System.Attribute::.ctor()
        IL_0006: nop
        IL_0007: ldarg.0
        IL_0008: ldc.i4.1
        IL_0009: newarr [System.Runtime]System.Byte
        IL_000e: dup
        IL_000f: ldc.i4.0
        IL_0010: ldarg.1
        IL_0011: stelem.i1
        IL_0012: stfld uint8[] System.Runtime.CompilerServices.NullableAttribute::NullableFlags
        IL_0017: ret
    } // end of method NullableAttribute::.ctor

    .method public hidebysig specialname rtspecialname 
        instance void .ctor (
            uint8[] ''
        ) cil managed 
    {
        // Method begins at RVA 0x2072
        // Code size 15 (0xf)
        .maxstack 8

        IL_0000: ldarg.0
        IL_0001: call instance void [System.Runtime]System.Attribute::.ctor()
        IL_0006: nop
        IL_0007: ldarg.0
        IL_0008: ldarg.1
        IL_0009: stfld uint8[] System.Runtime.CompilerServices.NullableAttribute::NullableFlags
        IL_000e: ret
    } // end of method NullableAttribute::.ctor

} // end of class System.Runtime.CompilerServices.NullableAttribute

.class private auto ansi sealed beforefieldinit System.Runtime.CompilerServices.NullableContextAttribute
    extends [System.Runtime]System.Attribute
{
    .custom instance void [System.Runtime]System.Runtime.CompilerServices.CompilerGeneratedAttribute::.ctor() = (
        01 00 00 00
    )
    .custom instance void Microsoft.CodeAnalysis.EmbeddedAttribute::.ctor() = (
        01 00 00 00
    )
    .custom instance void [System.Runtime]System.AttributeUsageAttribute::.ctor(valuetype [System.Runtime]System.AttributeTargets) = (
        01 00 4c 14 00 00 02 00 54 02 0d 41 6c 6c 6f 77
        4d 75 6c 74 69 70 6c 65 00 54 02 09 49 6e 68 65
        72 69 74 65 64 00
    )
    // Fields
    .field public initonly uint8 Flag

    // Methods
    .method public hidebysig specialname rtspecialname 
        instance void .ctor (
            uint8 ''
        ) cil managed 
    {
        // Method begins at RVA 0x2082
        // Code size 15 (0xf)
        .maxstack 8

        IL_0000: ldarg.0
        IL_0001: call instance void [System.Runtime]System.Attribute::.ctor()
        IL_0006: nop
        IL_0007: ldarg.0
        IL_0008: ldarg.1
        IL_0009: stfld uint8 System.Runtime.CompilerServices.NullableContextAttribute::Flag
        IL_000e: ret
    } // end of method NullableContextAttribute::.ctor

} // end of class System.Runtime.CompilerServices.NullableContextAttribute

.class private auto ansi sealed beforefieldinit System.Runtime.CompilerServices.RefSafetyRulesAttribute
    extends [System.Runtime]System.Attribute
{
    .custom instance void [System.Runtime]System.Runtime.CompilerServices.CompilerGeneratedAttribute::.ctor() = (
        01 00 00 00
    )
    .custom instance void Microsoft.CodeAnalysis.EmbeddedAttribute::.ctor() = (
        01 00 00 00
    )
    .custom instance void [System.Runtime]System.AttributeUsageAttribute::.ctor(valuetype [System.Runtime]System.AttributeTargets) = (
        01 00 02 00 00 00 02 00 54 02 0d 41 6c 6c 6f 77
        4d 75 6c 74 69 70 6c 65 00 54 02 09 49 6e 68 65
        72 69 74 65 64 00
    )
    // Fields
    .field public initonly int32 Version

    // Methods
    .method public hidebysig specialname rtspecialname 
        instance void .ctor (
            int32 ''
        ) cil managed 
    {
        // Method begins at RVA 0x2092
        // Code size 15 (0xf)
        .maxstack 8

        IL_0000: ldarg.0
        IL_0001: call instance void [System.Runtime]System.Attribute::.ctor()
        IL_0006: nop
        IL_0007: ldarg.0
        IL_0008: ldarg.1
        IL_0009: stfld int32 System.Runtime.CompilerServices.RefSafetyRulesAttribute::Version
        IL_000e: ret
    } // end of method RefSafetyRulesAttribute::.ctor

} // end of class System.Runtime.CompilerServices.RefSafetyRulesAttribute

​​.sharplab.json

{
    "version": 1,
    "target": "IL",
    "mode": "Debug"
}