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What is the optimal data structure for storing objects with a string key and a bool auxiliary value?

I need a data structure like below, but I need to be able to change the bool value. Other two stay the as they were when they were initialized. What would you use for best performance?
Dictionary<string, (object, bool)> dic = new Dictionary<string, (object, bool)>();
I was thinking of hashtable. But hashtable is like a dictionary with key/value. The object and bool in my example are in concept not like a key/value, because other values of the external dictionary can have the same object (or better yet ... object type). I don't want to make someone looking at my code later on thinking that the object and bool are more related they really are.
EDIT: object in this example is just a place holder. In reality it's a complex object with other objects in it and so on. Procedure before this one makes a bunch of this objects and some of them are deepcopy of the others. They are passed to this procedure. All of the object are here named by some rules and stored in the dictionary. Names are obviously unique. Procedure that comes after will take this dictionary and set the bool value on and off based on the values in the objects themselves and on the values of other bools. Procedure will be recursive until some state is reached.
Number of objects (or dic. entries) is arbitrary but expected to be >100 && <500. Time complexity is O(n).
I am targeting .NET7 (standard).

but I need to be able to change the bool value.
You can just reassign value for the key:
var tuples = new Dictionary<string, (object Obj, bool Bool)>
{
{ "1", (new object(), true) }
};
tuples["1"] = (tuples["1"].Obj, false); // or tuples["1"] = (tuples["1"].Item1, false);
Or
if (tuples.TryGetValue("1", out var c))
{
tuples["1"] = (c.Obj, false);
}
Personally I would leave it at that, but for really high perf scenarios you can look into CollectionMarshall instead of second snippet:
ref var v = ref CollectionsMarshal.GetValueRefOrNullRef(tuples, "1");
if (!Unsafe.IsNullRef(ref v))
{
v.Bool = false;
}
A bit more info - here.

For the 'performance' aspect:
The .NET Dictionary uses hashes to look up the item you need, which is very fast (comparable to a HashTable). I don't expect much performance issues related to this, or at least nothing that can be improved on with other data structures.
Also, you shouldn't worry about performance unless you are doing things a million times in a row + it turns out (in practice) that something is taking a measurable amount of time.
For the 'changing a bool' aspect:
... that is quite a long story.
There are 2 tuple variants in .NET:
The value tuple, created by doing var x = (myObj, myBool), like you are doing.
The x is a struct, and therefore a Value Type. You can actually change x.Item1 or x.Item2 to a new value just fine.
However... if you put x into a Dictionary then you actually put a copy of x (with a copy of its values) into the dictionary, because that is the nature of value types.
When you retrieve it again from the Dictionary, yet another copy is made - which makes modifying the actual tuple inside the Dictionary impossible; any attempt to do so would only modify the last copy you got.
Side story: The .NET Compiler knows this, which is why its refuses to compile code like dic[yourKey].Item2 = newBool; because such code wouldn't do what you might hope it would do. You're basically telling the compiler to create a copy, modify the copy, and then... discard the copy. The compiler requries a variable to store the copy before the rest can even start, but we provided no variable.
The Tuple generic class, or rather a range of generic classes, an instance of which can be created using calls like var x = Tuple.Create(myObj, myBool). These classes however forbid that you change any of their properties, they are always readonly. Tuple class instances can be put in a Dictionary, but they will still be readonly.
So what options are there really to 'modify a value in a tuple' a Dictionary?
Keep using a value tuple, but accept that in order to "change" the tuple inside the Dictionary you'll have to make a new instance (either a copy, or from scratch), set it to the properties that you want, and put that instance (or actualy a copy...) into the dictionary:
// initialize it
var dict = new Dictionary<string, (object, bool)>();
var obj = new object();
dict["abc"] = (obj, true);
// change it
var tmpTuple = dict["abc"]; // get copy
tmpTuple.Item2 = false; // alter copy
dict["abc"] = tmpTuple; // store another copy
// or if you want to avoid the tmp variable
dict["abc"] = (dict["abc"].Item1, false)
Use a custom class instead of the value tuple or a Tuple class, and then put that into the Dictionary:
public class MyPair
{
public object O { get; set; }
public bool B { get; set; }
}
// initialize it
var dict = new Dictionary<string, MyPair>();
var obj = new object();
dict["abc"] = new MyPair { O = obj, B = true };
// change it
dict["abc"].B = false;
So both types of Tuples are OK for objects that you don't want to do a lot with. But both have certain limits in their usage, and sooner or later you may need to start using classes.

How to sort a dictionary that contains dictionary?

I have a dictionary that contains another dictionary as value
something like this
Dictionary<string, Dictionary<double,double>>
now I want to sort it by internal dictionary's value
how can I do that??

From the looks of your comment
sorry i am not expert on c#, would you suggest a way to store 3 values as one item?
I would suggest creating a class and sort on it like this
public class MyClass
{
public string StringProperty {get;set;}
public int FirstDoubleProperty {get;set;}
public int SecondDoubleProperty {get;set;}
}
Then create a collection like this
List<MyClass> MyClasscol = new List<MyClass>();
MyClass mc = new MyClass();
mc.StringProperty = "User1225072";
mc.FirstDoubleProperty = 5;
mc.SecondDoubleProperty = 6;
MyClasscol.Add(mc);
mc = new MyClass();
// and So on
then sort like this
var newsortedcollection = MyClasscol.OrderBy(x => x.FirstDoubleProperty);

Assuming you are now trying to figure out how to store and order a collection of objects with multiple properties, then you have a few options. Nikhil Agrawal's answer is a great solution but there are times when you may not need/want to create a custom class for this. For these situations (preferably when your code is private and not part of some API) then the alternatives below might be an option.
KeyValuePairs
Based on your requirements and your original post using dictionaries, it seems like instead of a dictionary of dictionaries (multi-tiered), you probably wanted a dictionary of keyvaluepairs (flat).
// using keyvaluepair
var keyValueDict = new Dictionary<string, KeyValuePair<double, double>>();
keyValueDict.Add("string", new KeyValuePair<double, double>(5.8, 7.4));
var sortedKeyValues = keyValueDict.OrderBy(x => x.Value.Key);
Tuples
An alternative to the not so pleasant KeyValuePair is the Tuple introduced in .NET 4. The tuple is a generic class which allows you to store typed property values without creating your own custom class. It is worth noting that there are tuple implementations for up to 8 properties.
// using tuple
var tupleList = new List<Tuple<string, double, double>>();
tupleList.Add(new Tuple<string, double, double>("string", 5.8, 7.4));
var sortedTuples = tupleList.OrderBy(x => x.Item2);
There are some good SO questions about Tuples if you are interested:
Is Using .NET 4.0 Tuples in my C# Code a Poor Design Decision?
Are EventArg classes needed now that we have generics

Comparing dynamic objects in C#

What is the best way to compare two arbitrary dynamic objects for equality? For example these two objects.
I.e.
dynamic obj1 = new ExpandoObject();
obj1.Name = "Marcus";
obj1.Age = 39;
obj1.LengthInMeters = 1.96;
dynamic obj2 = AMethodReturningADynamic();
obj2.Name = "Marcus";
obj2.Age = 39;
obj2.LengthInMeters = 1.96;
Assert.AreEqual(obj1, obj2); // ?
Or is there a way to get the actual properties and their values as lists? To create an ExpandoObject from a dynamic type for example?

The Microsoft API's for dynamically invoking methods and propertys on arbitrary dynamic objects (IDynamicMetaObjectProvider) are not easy to use when you don't have the compiler's help. You can use Dynamitey (via nuget) to simplify this completely. It has a static function Dynamic.InvokeGet to call property's getters with just a target and a property name.
To get a list of properties of the dynamic object, there is a bit of a gotcha, as the dynamic object has to support it (if it's a DynamicObject that means implementing GetDynamicMemberNames, Expando supports it, but random IDynamicMetaObjectProvider may not and just return an empty list). Dynamitey has a method to simplifying getting those names as well, Dynamic.GetMemberNames.
Both of those two functions give you the basic tools necessary to compare many arbitrary dynamic objects via properties.
//using System.Dynamic;
//using Dynamitey;
//using System.Linq;
IEnumerable<string> list1 =Dynamic.GetMemberNames(obj1);
list1 = list1.OrderBy(m=>m);
IEnumerable<string> list2 =Dynamic.GetMemberNames(obj2);
list2 = list2.OrderBy(m=>m);
if(!list1.SequenceEqual(list2))
return false;
foreach(var memberName in list1){
if(!Dynamic.InvokeGet(obj1, memberName).Equals(Dynamic.InvokeGet(obj2,memberName))){
return false;
}
}
return true;
However, if they are just your own DynamicObject subclass then it'd be easier to just follow the typical rules for implementing Equals, there really is no difference from non-dynamic objects, and just compare what you are internally using for state.

ExpandoObject implements ICollection<KeyValuePair<string, object>> (in addition to IDictionary and IEnumerable of the same), so you should be able to compare them property by property pretty easily:
public static bool AreExpandosEquals(ExpandoObject obj1, ExpandoObject obj2)
{
var obj1AsColl = (ICollection<KeyValuePair<string,object>>)obj1;
var obj2AsDict = (IDictionary<string,object>)obj2;
// Make sure they have the same number of properties
if (obj1AsColl.Count != obj2AsDict.Count)
return false;
foreach (var pair in obj1AsColl)
{
// Try to get the same-named property from obj2
object o;
if (!obj2AsDict.TryGetValue(pair.Key, out o))
return false;
// Property names match, what about the values they store?
if (!object.Equals(o, pair.Value))
return false;
}
// Everything matches
return true;
}

See "Enumerating and deleting members" to get the members of an ExpandoObject http://msdn.microsoft.com/en-us/library/system.dynamic.expandoobject.aspx
Arbitrary dynamic objects do not appear to expose enumerators, though.

You have to implement IComparable-Interface. Then you have the appropriate functions needed from .NET/C# to compare two objects with each other.

Expando Objects are useable as an IDictonary<string, object> so you should be able to use that.
Something like
Assert.AreEqual((IDictonary(object, string))obj1, (IDictonary(object, string))obj2);
Edit the AreEqual won't work.
But you could try comparing the two dictionaries fairly simply.

You can also use the ObjectsComparer library available on GitHub :
ObjectsComparer
This library is an object-to-object comparer that allows us to compare objects recursively member by member and to define custom comparison rules for certain properties, fields or types. It supports enumerables (arrays, collections, lists), multidimensional arrays, enumerations, flags and dynamic objects (ExpandoObject, DynamicObject and compiler generated dynamic objects).
Go to Valerii Tereshchenko excellent paper for more details.

C# Defined Arrays

Can I define an array such that the first element is String, the Second is an int and the third is a textbox?
It's like when we create a List we choose type of element List<string >
Update from Comment:
Sorry I couldnt explain.I need to like
this List<string,int,object> Firstly i
will set type and when i call the list
i will not need to cast
thanks

create list of objects. in C# everything is derived from object
List<object> list = new List<object> {"first", 10, new TextBox()};
EDIT(To comment):
Then you should create seperate class to hold those three items , or use Tuple
List<Tuple<string,int,TextBox>> list;

You can declare an array of object and do that. You're talking about a mixed type array, right?
var arr = new object[] { "Hi", 42, 3.7, 'A' }

If you need an array that has elements without a common base-class other than object, then you're going to need an array of objects!
object[] myArray = new object[] { "Hi", 23, new TextBox() };
Note that this is not really something you should doing. If you need to associate disparate types like this, a class makes much more sense.

You want a Tuple<string,int,TextBox>, not an array.

IMHO the best way to do this is through a List<> of objects:
String s = "hey!";
int i = 156;
TextBox t = new TextBox();
List<object> list = new List<object>(3);
list.Add(s);
list.Add(i);
list.Add(t);
The reason this works is because (almost?) everything in C# derives from the base-class object

Arrays are typically homogeneous collections, which means that every object contains in the array is of the same type (or at least shares a common parent type). An array of [string, int, textbox] could be defined as an object[] but that's really misuse of arrays.
Just create a proper class which contains the 3 fields.
class MyType {
public string myString;
public int myInt;
public Listbox myListbox;
}

If you're looking make a list of string, int, textbox, you can either create a class which has those members or look at the Tuple class in .net 4.0
List<Tuple<string,int,TextBox>

Define a class that contains the 3 types then define an array that contains the new type.

Object[] myObjects = new Object(){"myString", 42, textbox1};

System.Collections.Generic.Dictionary<string, object> source = new System.Collections.Generic.Dictionary<string, object>();
source.Add("A", "Hi");
source.Add("B", 10);
source.Add("C", new TextBox());
While accessing
string str = Convert.ToString(source["A"]);
int id = Convert.ToInt16(source["B"]);
TextBox t = (TextBox)source["C"];

I will suggest that you create a Type such as
enum ItemType { Int, String, Textbox }
class MyType {
public object objValue;
public ItemType itemType;
}
List<MyType> list = new List<MyType>();
.......
You can iterate through the list or extract the list by type such as below.
var intList = list.Where(e=>e.itemType == ItemType.Int);
Of course you can achieve the above with the enum and using the reflected Type info directly from the object, but I just think it is clearer this way also more explicitly list out the type your list can hold rather than just all type in the CLR

C# properties as array notation

Using JavaScript it's possible to access an object using the dot notation or array notation.
var myArray = {e1:"elem1",e2:"elem2",e3:"elem3",e4:"elem4"};
var val1 = myArray["e1"];
var val2 = myArray.e1;
Is it possible to accomplish this using C#?
This is what I have attempted:
[AcceptVerbs(HttpVerbs.Post)]
public ActionResult Edit(int id, FormCollection frmVals)
{
string value;
Owner owner = new Owner();
foreach (var key in frmVals.AllKeys)
{
value = frmVals[key];
owner[key] = value;
}
}

While there is no way to do this exactly with C#. You could change your code in several ways that may accomplish your goal. First, you could use a Dictionary like this:
var something = new Dictionary<string, object>() {
{ "property", "value"},
{ "property1", 1}
};
foreach (var keyVal in something) {
var property = keyVal.Key;
var propertyValue = keyVal.Value;
}
Another option would be to do it dynamically:
dynamic somethingDyn = new System.Dynamic.ExpandoObject();
somethingDyn.property = "value";
somethingDyn.property1 = 1;
var somethingDynDict = (IDictionary<string, object>)somethingDyn;
var propValue = somethingDyn["property"];
foreach (var keyVal in somethingDynDict) {
var property = keyVal.Key;
var propertyValue = keyVal.Value;
}
If you need to iterate through properties on a strongly typed object you could use reflection:
var owner = new Metis.Domain.User();
var properties = owner.GetType().GetProperties();
foreach (var prop in properties) {
object value = prop.GetValue(owner, null);
}

I wouldn't recommend this, but you could put an indexer in your class, accepting a string, then use reflection to read that property. Something like:
public object this[string key]
{
get
{
var prop = typeof(ThisClassName).GetProperty(key);
if (prop != null)
{
return prop.GetValue(this, null);
}
return null;
}
set
{
var prop = typeof(ThisClassName).GetProperty(key);
if (prop != null)
{
prop.SetValue(this, value, null);
}
}
}

Javascript array notation is not something you can use in C#.
You need to use dot notation to access members of an object.
You will need to access each value directly and assign it:
owner.key = frmVals[key];
owner.key2 = frmVals[key2];
There are workarounds - using dictionaries, dynamic objects or even reflection, but the scenario is not a directly supported by C#.

There is no syntactic equivalent possible in C# but there are some ways to approximate the same feature.
You could mimic the indexer type access using a Dictionary but then you'd lose the property-style access. For property-style access, you could do something similar in C# by using an anonymous type, as in:
var myType = new { e1="elem1",e2="elem2",e3="elem3",e4="elem4"};
var val1 = myType.e1;
However, that doesn't create an array or allow array type access and it doesn't allow for modifications to the type after creation.
To get a closer approximation to the JavaScript feature, you may be able to use ExpandoObject to mimic this a little more closely, or you could implement something yourself.
For that, you'd need a class that has a constructor to auto-generate properties from the passed in array and exposes an indexer, which in turn uses reflection to find the named property.
Initialization of this type would be something like:
var myType = new MyType(new[]{
{"e1", "elem1"},
{"e2", "elem2"},
{"e3", "elem3"},
{"e4", "elem4"}});
This assumes there is a sub-type for each element definition (possibly using Tuple or KeyValuePair. The constructor would then be taking an IEnumerable<T> of that type.

Yes, it's possible.
There are two possibilities:
1) The list of keys and values is dynamic.
The array notation is provided by e.g. System.Collections.Generic.Dictionary<string, blah>
The member access notation can be provided through DLR magic and the dynamic keyword.
2) The list of keys and values is static.
Member access notation is already provided by the C# compiler.
Array notation can be had using Reflection (hopefully with a cache to improve performance).
In the static case, member access notation is MUCH faster. In the dynamic case, array notation will be a little faster.