.NET：CLR via C# A Brief Look at Metadata
基础知识
A managed PE file has four main parts: the PE32(+) header, the CLR header, the metadata, and the IL. The PE32(+) header is the standard information that Windows expects. The CLR header is a small block of information that is specific to modules that require the CLR (managed modules). The header includes the major and minor version number of the CLR that the module was built for: some flags, a MethodDef token (described later) indicating the module’s entry point method if this module is a CUI, GUI, or Windows Store executable, and an optional strong-name digital signature. Finally, the header contains the size and offsets of certain metadata tables contained within the module.
The metadata is a block of binary data that consists of several tables. There are three categories of tables: definition tables, reference tables, and manifest tables. T
Metadata table entries are also created as the compiler detects the types, fields, methods, properties, and events that the source code references. The metadata created includes a set of reference tables that keep a record of the referenced items.
示例
C# 代码
1 using System; 2 using System.Collections.Generic; 3 using System.Linq; 4 using System.Text; 5 using System.Threading.Tasks; 6 7 namespace Main 8 { 9 class Program 10 { 11 static void Main(string[] args) 12 { 13 Console.WriteLine(Type.GetType("A.ClassA, A")); 14 } 15 } 16 17 public class ClassMain 18 { 19 public string Property { get; set; } 20 21 public void Method(string msg) 22 { 23 Console.WriteLine(msg); 24 } 25 } 26 }
元数据
1 =========================================================== 2 ScopeName : Main.exe 3 MVID : {8C836651-F32E-4341-B87A-3479E4412916} 4 =========================================================== 5 Global functions 6 ------------------------------------------------------- 7 8 Global fields 9 ------------------------------------------------------- 10 11 Global MemberRefs 12 ------------------------------------------------------- 13 14 TypeDef #1 (02000002) 15 ------------------------------------------------------- 16 TypDefName: Main.Program (02000002) 17 Flags : [NotPublic] [AutoLayout] [Class] [AnsiClass] [BeforeFieldInit] (00100000) 18 Extends : 01000001 [TypeRef] System.Object 19 Method #1 (06000001) [ENTRYPOINT] 20 ------------------------------------------------------- 21 MethodName: Main (06000001) 22 Flags : [Private] [Static] [HideBySig] [ReuseSlot] (00000091) 23 RVA : 0x00002050 24 ImplFlags : [IL] [Managed] (00000000) 25 CallCnvntn: [DEFAULT] 26 ReturnType: Void 27 1 Arguments 28 Argument #1: SZArray String 29 1 Parameters 30 (1) ParamToken : (08000001) Name : args flags: [none] (00000000) 31 32 Method #2 (06000002) 33 ------------------------------------------------------- 34 MethodName: .ctor (06000002) 35 Flags : [Public] [HideBySig] [ReuseSlot] [SpecialName] [RTSpecialName] [.ctor] (00001886) 36 RVA : 0x00002063 37 ImplFlags : [IL] [Managed] (00000000) 38 CallCnvntn: [DEFAULT] 39 hasThis 40 ReturnType: Void 41 No arguments. 42 43 44 TypeDef #2 (02000003) 45 ------------------------------------------------------- 46 TypDefName: Main.ClassMain (02000003) 47 Flags : [Public] [AutoLayout] [Class] [AnsiClass] [BeforeFieldInit] (00100001) 48 Extends : 01000001 [TypeRef] System.Object 49 Field #1 (04000001) 50 ------------------------------------------------------- 51 Field Name: <Property>k__BackingField (04000001) 52 Flags : [Private] (00000001) 53 CallCnvntn: [FIELD] 54 Field type: String 55 CustomAttribute #1 (0c000001) 56 ------------------------------------------------------- 57 CustomAttribute Type: 0a000008 58 CustomAttributeName: System.Runtime.CompilerServices.CompilerGeneratedAttribute :: instance void .ctor() 59 Length: 4 60 Value : 01 00 00 00 > < 61 ctor args: () 62 63 64 Method #1 (06000003) 65 ------------------------------------------------------- 66 MethodName: get_Property (06000003) 67 Flags : [Public] [HideBySig] [ReuseSlot] [SpecialName] (00000886) 68 RVA : 0x0000206c 69 ImplFlags : [IL] [Managed] (00000000) 70 CallCnvntn: [DEFAULT] 71 hasThis 72 ReturnType: String 73 No arguments. 74 CustomAttribute #1 (0c000006) 75 ------------------------------------------------------- 76 CustomAttribute Type: 0a000008 77 CustomAttributeName: System.Runtime.CompilerServices.CompilerGeneratedAttribute :: instance void .ctor() 78 Length: 4 79 Value : 01 00 00 00 > < 80 ctor args: () 81 82 83 Method #2 (06000004) 84 ------------------------------------------------------- 85 MethodName: set_Property (06000004) 86 Flags : [Public] [HideBySig] [ReuseSlot] [SpecialName] (00000886) 87 RVA : 0x00002083 88 ImplFlags : [IL] [Managed] (00000000) 89 CallCnvntn: [DEFAULT] 90 hasThis 91 ReturnType: Void 92 1 Arguments 93 Argument #1: String 94 1 Parameters 95 (1) ParamToken : (08000002) Name : value flags: [none] (00000000) 96 CustomAttribute #1 (0c000007) 97 ------------------------------------------------------- 98 CustomAttribute Type: 0a000008 99 CustomAttributeName: System.Runtime.CompilerServices.CompilerGeneratedAttribute :: instance void .ctor() 100 Length: 4 101 Value : 01 00 00 00 > < 102 ctor args: () 103 104 105 Method #3 (06000005) 106 ------------------------------------------------------- 107 MethodName: Method (06000005) 108 Flags : [Public] [HideBySig] [ReuseSlot] (00000086) 109 RVA : 0x0000208c 110 ImplFlags : [IL] [Managed] (00000000) 111 CallCnvntn: [DEFAULT] 112 hasThis 113 ReturnType: Void 114 1 Arguments 115 Argument #1: String 116 1 Parameters 117 (1) ParamToken : (08000003) Name : msg flags: [none] (00000000) 118 119 Method #4 (06000006) 120 ------------------------------------------------------- 121 MethodName: .ctor (06000006) 122 Flags : [Public] [HideBySig] [ReuseSlot] [SpecialName] [RTSpecialName] [.ctor] (00001886) 123 RVA : 0x00002096 124 ImplFlags : [IL] [Managed] (00000000) 125 CallCnvntn: [DEFAULT] 126 hasThis 127 ReturnType: Void 128 No arguments. 129 130 Property #1 (17000001) 131 ------------------------------------------------------- 132 Prop.Name : Property (17000001) 133 Flags : [none] (00000000) 134 CallCnvntn: [PROPERTY] 135 hasThis 136 ReturnType: String 137 No arguments. 138 DefltValue: 139 Setter : (06000004) set_Property 140 Getter : (06000003) get_Property 141 0 Others 142 143 144 TypeRef #1 (01000001) 145 ------------------------------------------------------- 146 Token: 0x01000001 147 ResolutionScope: 0x23000001 148 TypeRefName: System.Object 149 MemberRef #1 (0a000007) 150 ------------------------------------------------------- 151 Member: (0a000007) .ctor: 152 CallCnvntn: [DEFAULT] 153 hasThis 154 ReturnType: Void 155 No arguments. 156 157 TypeRef #2 (01000002) 158 ------------------------------------------------------- 159 Token: 0x01000002 160 ResolutionScope: 0x23000001 161 TypeRefName: System.Runtime.Versioning.TargetFrameworkAttribute 162 MemberRef #1 (0a000001) 163 ------------------------------------------------------- 164 Member: (0a000001) .ctor: 165 CallCnvntn: [DEFAULT] 166 hasThis 167 ReturnType: Void 168 1 Arguments 169 Argument #1: String 170 171 TypeRef #3 (01000003) 172 ------------------------------------------------------- 173 Token: 0x01000003 174 ResolutionScope: 0x23000001 175 TypeRefName: System.Diagnostics.DebuggableAttribute 176 MemberRef #1 (0a000002) 177 ------------------------------------------------------- 178 Member: (0a000002) .ctor: 179 CallCnvntn: [DEFAULT] 180 hasThis 181 ReturnType: Void 182 1 Arguments 183 Argument #1: ValueClass DebuggingModes 184 185 TypeRef #4 (01000004) 186 ------------------------------------------------------- 187 Token: 0x01000004 188 ResolutionScope: 0x01000003 189 TypeRefName: DebuggingModes 190 191 TypeRef #5 (01000005) 192 ------------------------------------------------------- 193 Token: 0x01000005 194 ResolutionScope: 0x23000001 195 TypeRefName: System.Runtime.CompilerServices.CompilationRelaxationsAttribute 196 MemberRef #1 (0a000003) 197 ------------------------------------------------------- 198 Member: (0a000003) .ctor: 199 CallCnvntn: [DEFAULT] 200 hasThis 201 ReturnType: Void 202 1 Arguments 203 Argument #1: I4 204 205 TypeRef #6 (01000006) 206 ------------------------------------------------------- 207 Token: 0x01000006 208 ResolutionScope: 0x23000001 209 TypeRefName: System.Runtime.CompilerServices.RuntimeCompatibilityAttribute 210 MemberRef #1 (0a000004) 211 ------------------------------------------------------- 212 Member: (0a000004) .ctor: 213 CallCnvntn: [DEFAULT] 214 hasThis 215 ReturnType: Void 216 No arguments. 217 218 TypeRef #7 (01000007) 219 ------------------------------------------------------- 220 Token: 0x01000007 221 ResolutionScope: 0x23000001 222 TypeRefName: System.Type 223 MemberRef #1 (0a000005) 224 ------------------------------------------------------- 225 Member: (0a000005) GetType: 226 CallCnvntn: [DEFAULT] 227 ReturnType: Class System.Type 228 1 Arguments 229 Argument #1: String 230 231 TypeRef #8 (01000008) 232 ------------------------------------------------------- 233 Token: 0x01000008 234 ResolutionScope: 0x23000001 235 TypeRefName: System.Console 236 MemberRef #1 (0a000006) 237 ------------------------------------------------------- 238 Member: (0a000006) WriteLine: 239 CallCnvntn: [DEFAULT] 240 ReturnType: Void 241 1 Arguments 242 Argument #1: Object 243 MemberRef #2 (0a000009) 244 ------------------------------------------------------- 245 Member: (0a000009) WriteLine: 246 CallCnvntn: [DEFAULT] 247 ReturnType: Void 248 1 Arguments 249 Argument #1: String 250 251 TypeRef #9 (01000009) 252 ------------------------------------------------------- 253 Token: 0x01000009 254 ResolutionScope: 0x23000001 255 TypeRefName: System.Runtime.CompilerServices.CompilerGeneratedAttribute 256 MemberRef #1 (0a000008) 257 ------------------------------------------------------- 258 Member: (0a000008) .ctor: 259 CallCnvntn: [DEFAULT] 260 hasThis 261 ReturnType: Void 262 No arguments. 263 264 Signature #1 (0x11000001) 265 ------------------------------------------------------- 266 CallCnvntn: [LOCALSIG] 267 1 Arguments 268 Argument #1: String 269 270 Assembly 271 ------------------------------------------------------- 272 Token: 0x20000001 273 Name : Main 274 Public Key : 275 Hash Algorithm : 0x00008004 276 Version: 0.0.0.0 277 Major Version: 0x00000000 278 Minor Version: 0x00000000 279 Build Number: 0x00000000 280 Revision Number: 0x00000000 281 Locale: <null> 282 Flags : [none] (00000000) 283 CustomAttribute #1 (0c000002) 284 ------------------------------------------------------- 285 CustomAttribute Type: 0a000001 286 CustomAttributeName: System.Runtime.Versioning.TargetFrameworkAttribute :: instance void .ctor(class System.String) 287 Length: 73 288 Value : 01 00 1a 2e 4e 45 54 46 72 61 6d 65 77 6f 72 6b > .NETFramework< 289 : 2c 56 65 72 73 69 6f 6e 3d 76 34 2e 35 01 00 54 >,Version=v4.5 T< 290 : 0e 14 46 72 61 6d 65 77 6f 72 6b 44 69 73 70 6c > FrameworkDispl< 291 : 61 79 4e 61 6d 65 12 2e 4e 45 54 20 46 72 61 6d >ayName .NET Fram< 292 : 65 77 6f 72 6b 20 34 2e 35 >ework 4.5 < 293 ctor args: (".NETFramework,Version=v4.5") 294 295 CustomAttribute #2 (0c000003) 296 ------------------------------------------------------- 297 CustomAttribute Type: 0a000002 298 CustomAttributeName: System.Diagnostics.DebuggableAttribute :: instance void .ctor(value class DebuggingModes) 299 Length: 8 300 Value : 01 00 07 01 00 00 00 00 > < 301 ctor args: ( <can not decode> ) 302 303 CustomAttribute #3 (0c000004) 304 ------------------------------------------------------- 305 CustomAttribute Type: 0a000003 306 CustomAttributeName: System.Runtime.CompilerServices.CompilationRelaxationsAttribute :: instance void .ctor(int32) 307 Length: 8 308 Value : 01 00 08 00 00 00 00 00 > < 309 ctor args: (8) 310 311 CustomAttribute #4 (0c000005) 312 ------------------------------------------------------- 313 CustomAttribute Type: 0a000004 314 CustomAttributeName: System.Runtime.CompilerServices.RuntimeCompatibilityAttribute :: instance void .ctor() 315 Length: 30 316 Value : 01 00 01 00 54 02 16 57 72 61 70 4e 6f 6e 45 78 > T WrapNonEx< 317 : 63 65 70 74 69 6f 6e 54 68 72 6f 77 73 01 >ceptionThrows < 318 ctor args: () 319 320 321 AssemblyRef #1 (23000001) 322 ------------------------------------------------------- 323 Token: 0x23000001 324 Public Key or Token: b7 7a 5c 56 19 34 e0 89 325 Name: mscorlib 326 Version: 4.0.0.0 327 Major Version: 0x00000004 328 Minor Version: 0x00000000 329 Build Number: 0x00000000 330 Revision Number: 0x00000000 331 Locale: <null> 332 HashValue Blob: 333 Flags: [none] (00000000) 334 335 336 User Strings 337 ------------------------------------------------------- 338 70000001 : (11) L"A.ClassA, A" 339 340 341 Coff symbol name overhead: 0 342 =========================================================== 343 =========================================================== 344 ===========================================================
