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C# Equilavent of "dynamic" JavaScript object?

I want to create a single object (possibly Dictionary) with string keys that will have different variable types as the value (string, int, bool, Dictionary<string,string> etc). Is this possible?
*I understand this might just be a fundamental difference of two languages AKA square peg round hole

You can use dynamic as values type, that match better than object to the question and you need no future castings:
var dictionary = new Dictionary<string, dynamic>();
dictionary.Add("1", 10);
dictionary.Add("2", "test");
dictionary.Add("3", true);
foreach ( var item in dictionary )
Console.WriteLine($"{item.Key} is type: {item.Value.GetType().Name} = {item.Value}");
Console.WriteLine();
int v = dictionary["1"] + 10;
Console.WriteLine(v);
string s = dictionary["2"] + " one";
Console.WriteLine(s);
bool b = !dictionary["3"];
Console.WriteLine(b);
Output
1 is type: Int32 = 10
2 is type: String = test
3 is type: Boolean = True
20
test one
False
https://learn.microsoft.com/dotnet/csharp/programming-guide/types/using-type-dynamic

A Dictionary<string, object> is roughly equivalent to an object in JavaScript.
Example:
var dictionary = new Dictionary<string, object>
{
"myString" = "helloWorld",
"myChild" = new Dictionary<string, object>
{
"myName" = "bobby tables"
}
};
var myString = (string)dictionary["myString"];
var myName = (string)((Dictionary<string, object>)dictionary["myChild"])["myName"];
You can also use the dynamic keyword and ExpandoObject.
dynamic obj = new ExpandoObject();
obj.MyString = "helloWorld";
obj.MyChild = new ExpandoObject();
obj.MyChild.MyName = "bobby tables";
string myString = obj.MyString;
string myName = obj.MyChild.MyName;

String interpolation: How do I make this function work with any type

This is a function to work with lists in string interpolation. It takes a List and an inner Func, and it appends the string result of the inner Func called for each member of the list, with a separator.
So the following builds a valid start of an Insert statement...
static void Main(string[] args)
{
var tableName = "customers";
var cols = new List<dynamic>
{
new { Name = "surname"},
new { Name = "firstname"},
new { Name = "dateOfBirth"}
};
Func<List<dynamic>, Func<dynamic, string>, string, string> ForEach = (list, func, separator) =>
{
var bldr = new StringBuilder();
var first = true;
foreach (var obj in list)
{
if (!first)
bldr.Append(separator);
first = false;
bldr.Append(func(obj));
}
return bldr.ToString();
};
var InsertStatement = $"Insert into { tableName } ( {ForEach(cols, col => col.Name, ", ")} )";
Console.WriteLine(InsertStatement);
Console.ReadLine();
}
Outputs...
Insert into customers ( surname, firstname, dateOfBirth )
It works for dynamic. How do I make it work for any type? The outer Func shouldn't care about the Type in the list, it just passes it through to the inner Func.

The .NET framework already gives you a generic function to achieve what you are trying to do String.Join and you can combine it with a LINQ Select statement, which will allow you to use a lambda on a generic type to select the property that you want to print. You can view the source code of these methods if you are interested as they are open source.
using System;
using System.Collections.Generic;
using System.Linq;
public class MyType
{
public string Name { get; set; }
}
public class Program
{
public static void Main()
{
var tableName = "customers";
var cols = new List<MyType>
{
new MyType { Name = "surname"},
new MyType { Name = "firstname"},
new MyType { Name = "dateOfBirth"}
};
var InsertStatement = $"Insert into { tableName } ( {String.Join(", ", cols.Select(col => col.Name))} )";
Console.WriteLine(InsertStatement);
}
}

Replace dynamic with object, or TValue with a type constraint stipulating it must be a class (where TValue : class), and call obj.ToString() instead of just obj
However, this doesn't guarantee it would "work with any type" - for that you need to know that those types all follow a contract to output the desired column name as their string representation. To get more specificity, require that your accepted types must implement some interface eg IColumnName and put that interface into the type constraint instead

You can create the text easily like this:
var query = $"INSERT INTO {tableName}({string.Join(",", cols.Select(x=>x.Name))})";
However, if for learning purpose you are going to handle the case using a generic method, you can create a generic function like the following and then easily use a for loop and strip additional separator using TrimEnd, or as a better option, like String.Join implementation of .NET Framework get enumerator like this:
string Join<TItem>(
IEnumerable<TItem> items, Func<TItem, string> itemTextSelecor, string separator)
{
var en = items.GetEnumerator();
if (!en.MoveNext())
return String.Empty;
var builder = new StringBuilder();
if (en.Current != null)
builder.Append(itemTextSelecor(en.Current));
while (en.MoveNext())
{
builder.Append(separator);
if (en.Current != null)
builder.Append(itemTextSelecor(en.Current));
}
return builder.ToString();
}
And use it this way:
var tableName = "customers";
var cols = new[]
{
new { Name = "surname"},
new { Name = "firstname"},
new { Name = "dateOfBirth"}
};
var InsertStatement = $"INSERT INTO {tableName} ({Join(cols, col => col.Name, ", ")})"
+ $"VALUES({Join(cols, col => $"#{col.Name}", ", ")})";

Nested struct or class stored in a list in c#

is it possible to store nested structs or classes in lists using c#?
looking at the following code segments.
Nested Scruct:
struct structBooks
{
public string strBookName;
public string strAuthor;
public structPubished publishedDate;
}
struct structPubished
{
public int intDayOfMonth;
public int intMonthOfYear;
public int intYear;
}
saving as a list:
static void AddBookToList()
{
structBooks testStruct = new structBooks();
testStruct.strBookName = newBookName;
testStruct.strAuthor = newAuther;
testStruct.publishedDate.intYear = intNewYear;
testStruct.publishedDate.intMonthOfYear = intNewMonthOfYear;
testStruct.publishedDate.intDayOfMonth = intNewDayOfMonth;
static List<structBooks> listBooks = new List<structBooks>();
listBooks.Add(new structBooks()
{
strBookName = newBookName,
strAuthor = newAuther,
publishedDate.intYear = intNewYear,
publishedDate.intMonthOfYear = intNewMonthOfYear,
publishedDate.intDayOfMonth = intNewDayOfMonth
});
}
creating all the testStruct's works as expected.
When it comes to storing the struct as a list strBookName and strAuthor both work. However, when it comes to the nested publishedDate Visual Studio tells me "invalid initialiser member declarator".
the list its self is defined in the Main method, I just added it so you can see how it's defined.
what am i missing?

Use new to initialize your publishedDate struct, just as you do with structBooks.
List<structBooks> listBooks = new List<structBooks>();
listBooks.Add(new structBooks()
{
strBookName = "bookName",
strAuthor = "author",
publishedDate = new structPubished
{
intDayOfMonth = 1,
intMonthOfYear = 1,
intYear = 1000
}
});

You need to initialize your struct using the new keyword
List<structBooks> listBooks = new List<structBooks>();
listBooks.Add(new structBooks()
{
strBookName = "bookName",
strAuthor = "author",
publishedDate = new structPubished
{
intDayOfMonth = intNewDayOfMonth,
intMonthOfYear = intNewMonthOfYear,
intYear = intNewYear
}
});
Hope you also realize that you don't actually need to create the structPublished in the first place and could use in-build DateTime.
This would change your structBooks as
struct structBooks
{
public string strBookName;
public string strAuthor;
public DateTime publishedDate;
}
and you can add as
List<structBooks> listBooks = new List<structBooks>();
listBooks.Add(new structBooks()
{
strBookName = "bookName",
strAuthor = "author",
publishedDate = new DateTime(intNewYear,intNewMonthOfYear,intNewDayOfMonth)
});
The inbuild DateTime struct provides a lot of other functionalities which can be useful for your application.

Change this:
testStruct.publishedDate.intYear = intNewYear;
testStruct.publishedDate.intMonthOfYear = intNewMonthOfYear;
testStruct.publishedDate.intDayOfMonth = intNewDayOfMonth;
to this:
testStruct.publishedDate = new structPublished {
intYear = intNewYear,
intMonthOfYear = inNewMonthOfYear,
intDayOfMonth = intNewDayOfMonth
};
You can't initialise something by setting its fields or properties - C# still doesn't know the type of the thing you're trying to initialise. Instead, you need to use the new keyword which is designed for initialising objects.

This is the correct implementation:
static void AddBookToList()
{
structBooks testStruct = new structBooks();
testStruct.strBookName = newBookName;
testStruct.strAuthor = newAuther;
testStruct.publishedDate.intYear = intNewYear;
testStruct.publishedDate.intMonthOfYear = intNewMonthOfYear;
testStruct.publishedDate.intDayOfMonth = intNewDayOfMonth;
List<structBooks> listBooks = new List<structBooks>();
listBooks.Add(new structBooks()
{
strBookName = newBookName,
strAuthor = newAuther,
publishedDate = new structPubished()
{
intYear = intNewYear,
intMonthOfYear = intNewMonthOfYear,
intDayOfMonth = intNewDayOfMonth
}
});
}
The difference between the creation of testStruct and the one inserted to the list, is the way you initialize.
When you do
structBooks testStruct = new structBooks();
it initialize every object inside by using the default constructor, that's why you don't have to type
testStruct.publishedDate = new structPubished();
differently, when you declare the initialization by providing values of the Object, you must specify everything.

You need to use nested object initializer syntax. Notice there is no new keyword required to create the nested struct.
listBooks.Add
(
new structBooks
{
strBookName = newBookName,
strAuthor = newAuther,
publishedDate =
{
intYear = 2018,
intMonthOfYear = 1,
intDayOfMonth = 2
}
}
);

How do I add items to ASINList list?

I am trying out the Amazon MWS samples. How do I initialise request.ASINList with a list of ASINs?
My ASINs are in strings.
// Create a request.
GetLowestOfferListingsForASINRequest request = new GetLowestOfferListingsForASINRequest();
string sellerId = "example";
request.SellerId = sellerId;
string mwsAuthToken = "example";
request.MWSAuthToken = mwsAuthToken;
string marketplaceId = "example";
request.MarketplaceId = marketplaceId;
ASINListType asinList = new ASINListType();
request.ASINList = asinList;
string itemCondition = "example";
request.ItemCondition = itemCondition;
bool excludeMe = true;
request.ExcludeMe = excludeMe;
return this.client.GetLowestOfferListingsForASIN(request);
I can't seem to implicitly or explicitly cast a list or array of strings to ASINListType.

Don't know c# but in PHP you have to create an object of class "MarketplaceWebServiceProducts_Model_ASINListType"
e.g.
$asin_list = new MarketplaceWebServiceProducts_Model_ASINListType();
$asin_list->setASIN($asin_array);
$request->setASINList($asin_list);

Your request.ASINList needs to be assigned to an ASINListType. So instantiate that object, and assign your ASINs to it's ASIN property. This is just one way of doing it, but I typically do it very quickly this way:
var asinListType = new ASINListType();
asinListType.ASIN = new List<string> { "B00005TQI7", "B00AVO5XRK", etc, etc };
request.ASINList = asinListType;

Using a PropertyGrid to input method parameters

I'd like to use a PropertyGrid to input method parameters.
I have some application that will dynamically load user's DLLs and invoke methods with specific signature (a known return type).
I'd like to present the user the option to input the arguments to the called method easily with a PropertyGrid control.
Problem is -- PropertyGrid works on an Object, and not on a method.
I'd like to somehow "transform" the method at runtime into an object with properties reflecting its arguments, passing the input values to the method when invoking it.
Offcourse i'd like to have type validation, etc (if provided by the PropertyGrid, dont remember right now).
Is there any easy solution for this?
Thanks!

Well here is what I've written yesterday.
It is meant to be run in LinqPad, which is an awesome free tool to test linq queries or code snippets. (With an inexpensive upgrade to get intellisense)
The code should tell you how to deal with different kind of parameters (ref, out) and whether you are calling an instance method or not. (flip the comments in Main to test an instance method)
In LinqPad, you can use the Dump() extension method to let it show your objects in the results window. this is handy to see what is actually happening.
So, if you want to know how to dynamically construct a type and invoke it, this should get you started:
EDIT: I totally forgot to mention, that you do need to add these 2 namespaces to the query. You do that by hitting F4->additional namespace imports and adding these 2:
System.CodeDom.Compiler
System.CodeDom
public static String TestMethod1(int a, ref int X, out string t)
{
a += X;
X = a * 2;
t = "...>" + (X + a);
return a.ToString() + "...";
}
public class TestClass
{
public int SomeMethod(int a, DateTime? xyz)
{
if(xyz != null)
a+= xyz.GetValueOrDefault().Day;
return 12 + a;
}
}
void Main()
{
var sb = new StringBuilder();
var methodInfo = typeof(UserQuery).GetMethod("TestMethod1");
dynamic instance = CreateWrapper(methodInfo, sb);
instance.a = 11;
instance.X = 2;
instance.CallMethod();
/*
var methodInfo = typeof(TestClass).GetMethod("SomeMethod");
dynamic instance = CreateWrapper(methodInfo, sb);
instance.a = 11;
instance.xyz = new DateTime(2010, 1, 2);
instance.CallMethod(new TestClass());
*/
((Object)instance).Dump();
sb.ToString().Dump();
}
static object CreateWrapper(MethodInfo methodInfo, StringBuilder sb)
{
// pick either C#, VB or another language that can handle generics
var codeDom = CodeDomProvider.CreateProvider("C#");
var unit = new CodeCompileUnit();
var codeNameSpace = new CodeNamespace();
codeNameSpace.Name = "YourNamespace";
var wrapperType = AddWrapperType(codeDom, codeNameSpace, methodInfo, "WrapperType", "MethodResultValue");
unit.Namespaces.Add(codeNameSpace);
// this is only needed so that LinqPad can dump the code
codeDom.GenerateCodeFromNamespace(codeNameSpace, new StringWriter(sb), new CodeGeneratorOptions());
// put the temp assembly in LinqPad's temp folder
var outputFileName = Path.Combine(Path.GetDirectoryName(new Uri(typeof(UserQuery).Assembly.CodeBase).AbsolutePath),
Guid.NewGuid() + ".dll");
var results = codeDom.CompileAssemblyFromDom(new CompilerParameters(new[]{new Uri(methodInfo.DeclaringType.Assembly.CodeBase).AbsolutePath,
new Uri(typeof(UserQuery).Assembly.CodeBase).AbsolutePath,
new Uri(typeof(UserQuery).BaseType.Assembly.CodeBase).AbsolutePath}.Distinct().ToArray(),
outputFileName),
unit);
results.Errors.Dump();
new Uri(results.CompiledAssembly.CodeBase).AbsolutePath.Dump();
if(results.Errors.Count == 0)
{
var compiledType = results.CompiledAssembly.GetType(codeNameSpace.Name + "." + wrapperType.Name);
return Activator.CreateInstance(compiledType);
}
return null;
}
static CodeTypeDeclaration AddWrapperType(CodeDomProvider codeDom,
CodeNamespace codeNameSpace,
MethodInfo methodInfo,
string typeName,
string resultPropertyName)
{
var parameters = (from parameter in methodInfo.GetParameters()
select parameter).ToList();
var returnValue = methodInfo.ReturnType;
if(!String.IsNullOrEmpty(methodInfo.DeclaringType.Namespace))
codeNameSpace.Imports.Add(new CodeNamespaceImport(methodInfo.DeclaringType.Namespace));
var wrapperType = new CodeTypeDeclaration(typeName);
var defaultAttributes = MemberAttributes.Public | MemberAttributes.Final;
var thisRef = new CodeThisReferenceExpression();
Func<Type, Type> getRealType = t => t.IsByRef || t.IsPointer ? t.GetElementType(): t;
Func<String, String> getFieldName = parameterName => "m_" + parameterName + "_Field";
Action<ParameterInfo> addProperty = p =>
{
var realType = getRealType(p.ParameterType);
var usedName = p.Position == -1 ? resultPropertyName : p.Name;
wrapperType.Members.Add(new CodeMemberField
{
Name = getFieldName(usedName),
Type = new CodeTypeReference(realType),
Attributes= MemberAttributes.Private
});
var property = new CodeMemberProperty
{
Name = usedName,
Type = new CodeTypeReference(realType),
Attributes= defaultAttributes
};
property.GetStatements.Add(new CodeMethodReturnStatement(new CodeFieldReferenceExpression(thisRef,
getFieldName(usedName))));
property.SetStatements.Add(new CodeAssignStatement(new CodeFieldReferenceExpression(thisRef, getFieldName(usedName)),
new CodeArgumentReferenceExpression("value")));
wrapperType.Members.Add(property);
};
parameters.ForEach(addProperty);
if(methodInfo.ReturnParameter != null)
{
addProperty(methodInfo.ReturnParameter);
}
var callMethod = new CodeMemberMethod
{
Name="CallMethod",
Attributes=defaultAttributes
};
CodeMethodInvokeExpression invokeExpr;
if(!methodInfo.IsStatic)
{
callMethod.Parameters.Add(new CodeParameterDeclarationExpression(methodInfo.DeclaringType,
"instance"));
invokeExpr = new CodeMethodInvokeExpression(new CodeArgumentReferenceExpression("instance"),
methodInfo.Name);
}
else
invokeExpr = new CodeMethodInvokeExpression(new CodeTypeReferenceExpression(methodInfo.DeclaringType), methodInfo.Name);
foreach(var parameter in parameters)
{
CodeExpression fieldExpression = new CodeFieldReferenceExpression(thisRef,
getFieldName(parameter.Name));
if(parameter.ParameterType.IsByRef && !parameter.IsOut)
fieldExpression = new CodeDirectionExpression(FieldDirection.Ref, fieldExpression);
else if(parameter.IsOut)
fieldExpression = new CodeDirectionExpression(FieldDirection.Out, fieldExpression);
else if(parameter.IsIn)
fieldExpression = new CodeDirectionExpression(FieldDirection.In, fieldExpression);
invokeExpr.Parameters.Add(fieldExpression);
}
wrapperType.Members.Add(callMethod);
if(returnValue != typeof(void))
callMethod.Statements.Add(new CodeAssignStatement(new CodeFieldReferenceExpression(thisRef,
getFieldName(resultPropertyName)),
invokeExpr));
else
callMethod.Statements.Add(invokeExpr);
codeNameSpace.Types.Add(wrapperType);
return wrapperType;
}

I think you could add a new class to your project that implement the ICustomTypeDescriptor interface. And use the instance of this class as the wrapper of your method parameters.
Here is an article shows how to custom property grid display by implementing ICustomTypeDescriptor.