ExportMethods.il

.assembly extern mscorlib { auto }
.assembly YDD { }
.module YDD.dll
.corflags 0x00000002
.vtfixup [1] int32 fromunmanaged at VT_01 // First v-table fixup
.vtfixup [1] int32 fromunmanaged at VT_02 // Second v-table fixup
.vtfixup [1] int32 fromunmanaged at VT_03 // Third v-table fixup
.data VT_01 = int32(0) // First v-table entry
.data VT_02 = int32(0) // Second v-table entry
.data VT_03 = int32(0) // Third v-table entry
.method public static void Yabba()
{
    .vtentry 1:1
    .export [1]
    ldstr "Yabba"
    call void [mscorlib]System.Console::WriteLine(string)
    ret
}
.method public static void Dabba()
{
    .vtentry 2:1
    .export [2]
    ldstr "Dabba"
    call void [mscorlib]System.Console::WriteLine(string)
    ret
}
.method public static void Doo()
{
    .vtentry 3:1
    .export [3]
    ldstr "Doo!"
    call void [mscorlib]System.Console::WriteLine(string)
    ret
}

How to compile:

ilasm /dll ExportMethods.il /out:ExportMethods.dll

Result

// Result of "dumpbin /exports ExportMethods.dll"

Microsoft (R) COFF/PE Dumper Version 14.00.23918.0
Copyright (C) Microsoft Corporation.  All rights reserved.


Dump of file ExportMethods.dll

File Type: DLL

  Section contains the following exports for ExportMethods.dll

    00000000 characteristics
    57A99911 time date stamp Tue Aug  9 17:49:21 2016
        0.00 version
           1 ordinal base
           3 number of functions
           3 number of names

    ordinal hint RVA      name

          2    0 0000223E Dabba
          3    1 0000224E Doo
          1    2 0000222E Yabba

  Summary

        2000 .reloc
        2000 .sdata
        2000 .text