How do I check if a property exists on a dynamic anonymous type in c

Question

I have an anonymous type object that I receive as a dynamic from a method I would like to check in a property exists on that object        var settings   new                      Filename  temp txt                      Size 10        function void Settings dynamic settings    var exists   IsSettingExist settings  Filename       How would I implement IsSettingExist

User · Answer

To extend the answer from  Kuroro  if you need to test if the property is empty  below should work   public static bool PropertyExistsAndIsNotNull dynamic obj  string name        if  obj    null  return false      if  obj is ExpandoObject                if    IDictionary lt string  object gt  obj  ContainsKey name               return   IDictionary lt string  object gt  obj  name     null          return false            if  obj is IDictionary lt string  object gt  dict1                if  dict1 ContainsKey name               return dict1 name     null          return false            if  obj is IDictionary lt string  JToken gt  dict2                if  dict2 ContainsKey name               return  dict2 name  Type    JTokenType Null  amp  amp  dict2 name  Type    JTokenType Undefined           return false            if  obj GetType   GetProperty name     null          return obj GetType   GetProperty name  GetValue obj     null      return false

User · Answer

Using reflection  this is the function i use    public static bool doesPropertyExist dynamic obj  string property        return   Type obj GetType    GetProperties   Where p   gt  p Name Equals property   Any        then    if  doesPropertyExist myDynamicObject   myProperty

User · Answer

public static void Test                 int LOOP LENGTH   100000000                        long first memory   GC GetTotalMemory true               var stopWatch   Stopwatch StartNew                 Console WriteLine  quot doesPropertyExist quot                 dynamic testdo   new   A   1  B    string null  C    quot A quot                 for  int i   0  i  lt  LOOP LENGTH  i                                  if   TestDynamic doesPropertyExist testdo   quot A quot                                          Console WriteLine  quot throw find quot                        break                                     if  TestDynamic doesPropertyExist testdo   quot ABC quot                                          Console WriteLine  quot throw not find quot                        break                                              stopWatch Stop                var last memory   GC GetTotalMemory true               Console WriteLine   quot  Time  stopWatch Elapsed TotalSeconds s t Memory  last memory - first memory  quot                                     long first memory   GC GetTotalMemory true               var stopWatch   Stopwatch StartNew                 Console WriteLine  quot HasProperty quot                 dynamic testdo   new   A   1  B    string null  C    quot A quot                 for  int i   0  i  lt  LOOP LENGTH  i                                  if   TestDynamic HasProperty testdo   quot A quot                                          Console WriteLine  quot throw find quot                        break                                     if  TestDynamic HasProperty testdo   quot ABC quot                                          Console WriteLine  quot throw not find quot                        break                                              stopWatch Stop                var last memory   GC GetTotalMemory true               Console WriteLine   quot  Time  stopWatch Elapsed TotalSeconds s t Memory  last memory - first memory  quot                                      long first memory   GC GetTotalMemory true               var stopWatch   Stopwatch StartNew                 Console WriteLine  quot IsPropertyExist quot                 dynamic testdo   new   A   1  B    string null  C    quot A quot                 for  int i   0  i  lt  LOOP LENGTH  i                                  if   TestDynamic IsPropertyExist testdo   quot A quot                                          Console WriteLine  quot throw find quot                        break                                     if  TestDynamic IsPropertyExist testdo   quot ABC quot                                          Console WriteLine  quot throw not find quot                        break                                              stopWatch Stop                var last memory   GC GetTotalMemory true               Console WriteLine   quot  Time  stopWatch Elapsed TotalSeconds s t Memory  last memory - first memory  quot                                     long first memory   GC GetTotalMemory true               var stopWatch   Stopwatch StartNew                 Console WriteLine  quot IsPropertyExistBinderException quot                 dynamic testdo   new   A   1  B    string null  C    quot A quot                 for  int i   0  i  lt  LOOP LENGTH  i                                  if   TestDynamic IsPropertyExistBinderException testdo   quot A quot                                          Console WriteLine  quot throw find quot                        break                                     if  TestDynamic IsPropertyExistBinderException testdo   quot ABC quot                                          Console WriteLine  quot throw not find quot                        break                                              stopWatch Stop                var last memory   GC GetTotalMemory true               Console WriteLine   quot  Time  stopWatch Elapsed TotalSeconds s t Memory  last memory - first memory  quot                                      long first memory   GC GetTotalMemory true               var stopWatch   Stopwatch StartNew                 Console WriteLine  quot PropertyExists quot                 dynamic testdo   new   A   1  B    string null  C    quot A quot                 for  int i   0  i  lt  LOOP LENGTH  i                                  if   TestDynamic PropertyExists testdo   quot A quot                                          Console WriteLine  quot throw find quot                        break                                     if  TestDynamic PropertyExists testdo   quot ABC quot                                          Console WriteLine  quot throw not find quot                        break                                              stopWatch Stop                var last memory   GC GetTotalMemory true               Console WriteLine   quot  Time  stopWatch Elapsed TotalSeconds s t Memory  last memory - first memory  quot                                      long first memory   GC GetTotalMemory true               var stopWatch   Stopwatch StartNew                 Console WriteLine  quot PropertyExistsJToken quot                 dynamic testdo   new   A   1  B    string null  C    quot A quot                 for  int i   0  i  lt  LOOP LENGTH  i                                  if   TestDynamic PropertyExistsJToken testdo   quot A quot                                          Console WriteLine  quot throw find quot                        break                                     if  TestDynamic PropertyExistsJToken testdo   quot ABC quot                                          Console WriteLine  quot throw not find quot                        break                                              stopWatch Stop                var last memory   GC GetTotalMemory true               Console WriteLine   quot  Time  stopWatch Elapsed TotalSeconds s t Memory  last memory - first memory  quot                             public static bool IsPropertyExist dynamic settings  string name                if  settings is ExpandoObject              return   IDictionary lt string  object gt  settings  ContainsKey name            return settings GetType   GetProperty name     null             public static bool HasProperty dynamic obj  string name                Type objType   obj GetType             if  objType    typeof ExpandoObject                         return   IDictionary lt string  object gt  obj  ContainsKey name                      return objType GetProperty name     null              public static bool PropertyExists dynamic obj  string name                if  obj    null  return false          if  obj is IDictionary lt string  object gt  dict                        return dict ContainsKey name                     return obj GetType   GetProperty name     null                public static bool HasPropertyExist dynamic settings  string name                      if  settings is System Dynamic ExpandoObject                 return   IDictionary lt string  object gt  settings  ContainsKey name              if  settings is DynamicJsonObject                 try                                     return settings name     null                                  catch  KeyNotFoundException                                      return false                              return settings GetType   GetProperty name     null                public static bool IsPropertyExistBinderException dynamic dynamicObj  string property                try                       var value   dynamicObj property  Value              return true                    catch  RuntimeBinderException                         return false                        public static bool HasPropertyFoundException dynamic obj  string name                try                       var value   obj name               return true                    catch  KeyNotFoundException                        return false                        public static bool doesPropertyExist dynamic obj  string property                return   Type obj GetType    GetProperties   Where p   gt  p Name Equals property   Any               public static bool PropertyExistsJToken dynamic obj  string name                if  obj    null  return false          if  obj is ExpandoObject              return   IDictionary lt string  object gt  obj  ContainsKey name           if  obj is IDictionary lt string  object gt  dict1              return dict1 ContainsKey name           if  obj is IDictionary lt string  JToken gt  dict2              return dict2 ContainsKey name           return obj GetType   GetProperty name     null                public static bool PropertyExistsJsonObject dynamic settings  string name                      if  settings is ExpandoObject                 return   IDictionary lt string  object gt  settings  ContainsKey name              else if  settings is DynamicJsonObject                 return   DynamicJsonObject settings  GetDynamicMemberNames   Contains name               return settings GetType   GetProperty name     null              doesPropertyExist Time 59 5907507s        Memory 403680 HasProperty Time 30 8231781s        Memory 14968 IsPropertyExist Time 39 6179575s        Memory 97000 IsPropertyExistBinderException throw find PropertyExists Time 56 009761s         Memory 13464 PropertyExistsJToken Time 61 6146953s        Memory 15952

User · Answer

Merging and fixing answers from Serj-TM and user3359453 so that it works with both ExpandoObject and DynamicJsonObject  This works for me   public static bool HasPropertyExist dynamic settings  string name        if  settings is System Dynamic ExpandoObject          return   IDictionary lt string  object gt  settings  ContainsKey name        if  settings is System Web Helpers DynamicJsonObject      try               return settings name     null            catch  KeyNotFoundException                return false              return settings GetType   GetProperty name     null

User · Answer

This works for anonymous types  ExpandoObject  Nancy DynamicDictionary or anything else that can be cast to IDictionary lt string  object gt        public static bool PropertyExists dynamic obj  string name            if  obj    null  return false          if  obj is IDictionary lt string  object gt  dict                return dict ContainsKey name                     return obj GetType   GetProperty name     null

User · Answer

public static bool HasProperty dynamic obj  string name        Type objType   obj GetType         if  objType    typeof ExpandoObject                 return   IDictionary lt string  object gt  obj  ContainsKey name              return objType GetProperty name     null

User · Answer

I m not sure why these answer are so complex  try  dynamic settings   new                               Filename    quot temp txt quot                   Size   10                 string fileName   settings Filename   var fileNameExists   fileName    null

User · Answer

In case someone need to handle a dynamic object come from Json  I has modified Seth Reno answer to handle dynamic object deserialized from NewtonSoft Json JObjcet   public static bool PropertyExists dynamic obj  string name                if  obj    null  return false          if  obj is ExpandoObject              return   IDictionary lt string  object gt  obj  ContainsKey name           if  obj is IDictionary lt string  object gt  dict1              return dict1 ContainsKey name           if  obj is IDictionary lt string  JToken gt  dict2              return dict2 ContainsKey name           return obj GetType   GetProperty name     null

User · Answer

public static bool IsPropertyExist dynamic settings  string name          if  settings is ExpandoObject        return   IDictionary lt string  object gt  settings  ContainsKey name        return settings GetType   GetProperty name     null         var settings   new  Filename     c  temp q txt      Console WriteLine IsPropertyExist settings   Filename       Console WriteLine IsPropertyExist settings   Size       Output    True  False

User · Answer

if you can control creating passing the settings object  i d recommend using an ExpandoObject instead   dynamic settings   new ExpandoObject    settings Filename    asdf txt   settings Size   10       function void Settings dynamic settings        if     IDictionary lt string  object gt  settings  ContainsKey  Filename                  do something

User · Answer

None of the solutions above worked for dynamic that comes from Json  I however managed to transform one with Try catch  by  user3359453  by changing exception type thrown  KeyNotFoundException instead of RuntimeBinderException  into something that actually works      public static bool HasProperty dynamic obj  string name                try                       var value   obj name               return true                    catch  KeyNotFoundException                        return false                      Hope this saves you some time

User · Answer

This works also for DynamicJsonObject    public static bool PropertyExists dynamic settings  string name          if  settings is ExpandoObject        return   IDictionary lt string  object gt  settings  ContainsKey name       else if  settings is DynamicJsonObject        return   DynamicJsonObject settings  GetDynamicMemberNames   Contains name        return settings GetType   GetProperty name     null

User · Answer

This is working for me-     public static bool IsPropertyExist dynamic dynamicObj  string property                      try                             var value dynamicObj property  Value                 return true                          catch  RuntimeBinderException                               return false

[c#] How do I check if a property exists on a dynamic anonymous type in c#?

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