只是一点设置。我们安装了.Net framework 3.5,4.0,4.5和4.6.1。
如果我们使用.Net framework 3.5构建.Net应用程序或程序集，然后我们将app.config设置为使用4.6.1的单个受支持的运行时运行：
<startup><supportedRuntime version="v4.0" sku=".NETFramework,Version=v4.6.1"/></startup>
实际使用了哪个版本的框架？
这个问题来自于阅读这篇文章：How do I force an application compiled to target .NET Framework 4 to run under .NET framework 4.6.1?。 @Hans Passant声明TargetFrameworkAttribute将决定框架的行为方式，并且他谈到有导致特定代码运行的开关等等。但是，我还没有找到任何解释核心.Net框架版本的东西在这种情况下运行。
对.Net框架的任何调用是否都使用.Net 3.5代码库，.Net 4.0代码库（因为4.0 clr版本），或者是否会运行最新和最好的.Net 4.6.1代码库，因为这是使用clr 4.0安装的最新版本？
编辑：显示未明确说明运行时版本的清单。
// Metadata version: v2.0.50727
.assembly extern mscorlib
{
.publickeytoken = (B7 7A 5C 56 19 34 E0 89 ) // .z\V.4..
.ver 2:0:0:0
}
.assembly ConsoleApplicationVersionTest
{
.custom instance void [mscorlib]System.Runtime.CompilerServices.CompilationRelaxationsAttribute::.ctor(int32) = ( 01 00 08 00 00 00 00 00 )
.custom instance void [mscorlib]System.Runtime.CompilerServices.RuntimeCompatibilityAttribute::.ctor() = ( 01 00 01 00 54 02 16 57 72 61 70 4E 6F 6E 45 78 // ....T..WrapNonEx
63 65 70 74 69 6F 6E 54 68 72 6F 77 73 01 ) // ceptionThrows.
// --- The following custom attribute is added automatically, do not uncomment -------
// .custom instance void [mscorlib]System.Diagnostics.DebuggableAttribute::.ctor(valuetype [mscorlib]System.Diagnostics.DebuggableAttribute/DebuggingModes) = ( 01 00 07 01 00 00 00 00 )
.custom instance void [mscorlib]System.Reflection.AssemblyTitleAttribute::.ctor(string) = ( 01 00 1D 43 6F 6E 73 6F 6C 65 41 70 70 6C 69 63 // ...ConsoleApplic
61 74 69 6F 6E 56 65 72 73 69 6F 6E 54 65 73 74 // ationVersionTest
00 00 )
.custom instance void [mscorlib]System.Reflection.AssemblyDescriptionAttribute::.ctor(string) = ( 01 00 00 00 00 )
.custom instance void [mscorlib]System.Reflection.AssemblyConfigurationAttribute::.ctor(string) = ( 01 00 00 00 00 )
.custom instance void [mscorlib]System.Reflection.AssemblyCompanyAttribute::.ctor(string) = ( 01 00 00 00 00 )
.custom instance void [mscorlib]System.Reflection.AssemblyProductAttribute::.ctor(string) = ( 01 00 1D 43 6F 6E 73 6F 6C 65 41 70 70 6C 69 63 // ...ConsoleApplic
61 74 69 6F 6E 56 65 72 73 69 6F 6E 54 65 73 74 // ationVersionTest
00 00 )
.custom instance void [mscorlib]System.Reflection.AssemblyCopyrightAttribute::.ctor(string) = ( 01 00 12 43 6F 70 79 72 69 67 68 74 20 C2 A9 20 // ...Copyright ..
20 32 30 31 36 00 00 ) // 2016..
.custom instance void [mscorlib]System.Reflection.AssemblyTrademarkAttribute::.ctor(string) = ( 01 00 00 00 00 )
.custom instance void [mscorlib]System.Runtime.InteropServices.ComVisibleAttribute::.ctor(bool) = ( 01 00 00 00 00 )
.custom instance void [mscorlib]System.Runtime.InteropServices.GuidAttribute::.ctor(string) = ( 01 00 24 34 36 36 31 33 34 32 33 2D 38 39 34 30 // ..$46613423-8940
2D 34 39 36 65 2D 61 31 37 32 2D 37 36 36 31 31 // -496e-a172-76611
64 30 66 31 32 32 38 00 00 ) // d0f1228..
.custom instance void [mscorlib]System.Reflection.AssemblyFileVersionAttribute::.ctor(string) = ( 01 00 07 31 2E 30 2E 30 2E 30 00 00 ) // ...1.0.0.0..
.hash algorithm 0x00008004
.ver 1:0:0:0
}
.module ConsoleApplicationVersionTest.exe
// MVID: {11493526-C9AC-45F0-9784-D7712809998C}
.imagebase 0x00400000
.file alignment 0x00000200
.stackreserve 0x00100000
.subsystem 0x0003 // WINDOWS_CUI
.corflags 0x00000001 // ILONLY
// Image base: 0x00000000010B0000