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How to retrieve first row from dictionary in C#?

How to retrieve first row from this dictionary. I put around some 15 records.
Dictionary<string, Tuple<string, string>> headINFO =
new Dictionary<string, Tuple<string, string>> { };

You can use headINFO.First(), but unless you know that there always will be at least one entry in headINFO I would recommend that you use headINFO.FirstOrDefault().
More information on the differences between the two available here.
Edit: Added simple examples
Here is a quick example on how to use FirstOrDefault()
var info = headINFO.FirstOrDefault().Value;
Console.WriteLine(info.Item1); // Prints Tuple item1
Console.WriteLine(info.Item2); // Prints Tuple item2
If you want to print multiple items you can use Take(x). In this case we will loop through three dictionary items, but you can easily modify the number to grab more items.
foreach (var info in headINFO.Take(3))
{
Console.WriteLine(info.Value.Item1);
Console.WriteLine(info.Value.Item2);
}
You should also keep in mind that the above foreach does not allow you to modify the values of your Dictionary entries directly.
Edit2: Clarified usage of First() and added clean foreach example
Keep in mind that while First() and FirstOrDefault() will provide you with a single item it does in no way guarantee that it will be the first item added.
Also, if you simply want to loop through all the items you can remove the Take(3) in the foreach loop mentioned above.
foreach (var info in headINFO)
{
Console.WriteLine(info.Key); // Print Dictionary Key
Console.WriteLine(info.Value.Item1); // Prints Turple Value 1
Console.WriteLine(info.Value.Item2); // Prints Turple Value 2
}

Dictionaries are unordered, so there is no way to retrieve the first key-value pair you inserted.
You can retrieve an item by calling the LINQ .First() method.

The easiest way is just to use Linq's First extension method:
var firstHead = headINFO.First();
Or if you want to be safer, the FirstOrDefault method will return null if the dictionary is empty:
var firstHead = headINFO.FirstOrDefault();
If you'd like to loop through all items in the dictionary, try this:
foreach(var head in headINFO)
{
...
}

Try this code.
headINFO.FirstOrDefault();

Try this:
int c=0;
foreach(var item in myDictionary)
{
c++;
if(c==1)
{
myFirstVar = item.Value;
}
else if(c==2)
{
mySecondVar = item.Value;
}
......
}

Navigate through dictionary <string, int> c#

What is the better way to Navigate through a dictionary ? I used to use the code below when i had IDictionary:
Assume that I have IDictionary named freq
IEnumerator enums = freq.GetEnumerator();
while (enums.MoveNext())
{
string word = (string)enums.Key;
int val = (int)enums.Value;
.......... and so on
}
but now, I want to do the same thing using dictionary

The default enumerator from a foreach gives you a KeyValuePair<TKey, TValue>:
foreach (var item in dictionary)
// foreach (KeyValuePair<string, int> item in dictionary)
{
var key = item.Key;
var value = item.Value;
}
This simply compiles into code that works directly with the enumerator as in your old code.
Or you can enumerate the .Keys or .Values directly (but you only get a key or a value in that case):
foreach (var key in dictionary.Keys)
foreach (var val in dictionary.Values)
And or course linq works against dictionaries:
C# linq in Dictionary<>

Well you could do the same thing with Dictionary, but it would be cleaner to use foreach in both cases:
foreach (var entry in dictionary)
{
string key = entry.Key;
int value = entry.Value;
// Use them...
}
This is equivalent to:
using (var iterator = dictionary.GetEnumerator())
{
while (iterator.MoveNext())
{
var entry = iterator.Current;
string key = entry.Key;
int value = entry.Value;
// Use them...
}
}
It's very rarely useful to explicitly call GetEnumerator and iterate yourself. It's appropriate in a handful of cases, such as when you want to treat the first value differently, but if you're going to treat all entries the same way, use foreach.
(Note that it really is equivalent to using var here, but not equivalent to declaring an IEnumerator<KeyValuePair<string, int>> - it will actually use the nested Dictionary.Enumerator struct. That's a detail you usually don't need to worry about.)

The foreach statement iterates automatically through enumerators.
foreach (KeyValuePair<string,int> entry in freq) {
string word = entry.Key;
int val = entry.Value;
.......... and so on
}

How to compare two Dictionary<string,int> to find if any of the value has changed?

I have two dictionary personalizePatientChartDictionary and personalizePatientChartDictionaryOriginal. Both have same key but value can be different. I want to find out if there is any difference in value for a key. I have come up with the following function. Is there any better way of doing this? I am using .NET 4.0.
void CompareOriginalValues()
{
foreach (KeyValuePair<string, int> Origkvp in personalizePatientChartDictionaryOriginal)
{
foreach (KeyValuePair<string, int> kvp in personalizePatientChartDictionary)
{
if ((Origkvp.Key == kvp.Key) && (Origkvp.Value != kvp.Value))
{
hasDictionaryChanged = true;
break;
}
}
if (hasDictionaryChanged)
{
break;
}
}
}

foreach (var kvp in personalizePatientChartDictionaryOriginal)
{
int value;
if (personalizePatientChartDictionary.TryGetValue(kvp.Key, out value))
{
if (kvp.Value != value)
{
hasDictionaryChanged = true;
break;
}
}
}
Note that this code (and your original code) don't detect if there are keys in one dictionary that aren't present in the other. It only checks that the value associated with a particular key in the first dictionary is associated with the same key in the second dictionary, but only if that key actually exists in the second dictionary.

Seems good. But it would be good to return hasDictionaryChanged to indicate that it changed

You can do it using LINQ (don't forget to add "using System.Linq" to your usings)
bool hasDictionaryChanged = personalizePatientChartDictionaryOriginal.Except(personalizePatientChartDictionary).Count() > 0;
For more information about what you can do with LINQ, see 101 LINQ Samples.

It would be possible to write your own version of the dictionary class, inherit from dictionary and IComparable.
Then you could do dictionary1.Compare(dictionary2);
Here is a good resource for the ICompareable interface
http://msdn.microsoft.com/en-us/library/system.icomparable.aspx

The best way to use dictionary items as we use the advantages of List

I want to get use of dictionary items like I do in List generic class,
e.g;
foreach(item in ItemList)
{
item.BlaBla;
}
But in dictionary there s no chance, like e method above...
Dictionary<string, HtmlInputImage> smartPenImageDictionary;
I mean I got to know the key item for the dictionary item.. but what I want, I want to travel from beginning of the list till the end..

I am not absolutely sure what you want to achieve but here are the common things you can do with a dictionary.
IDictionary<Int32, String> dictionary = new Dictionary<Int32, String>();
// Iterate over all key value pairs.
foreach (KeyValuePair<Int32, String> keyValuePair in dictionary)
{
Int32 key = keyValuePair.Key;
String value = keyValuePair.Value;
}
// Iterate over all keys.
foreach (Int32 key in dictionary.Keys)
{
// Get the value by key.
String value = dictionary[key];
}
// Iterate over all values.
foreach (String value in dictionary.Values)
{
}

Iterating over a dictionary results in KeyValuePair<>s. Simply access the Key and Value members of the appropriate variable.

Something like this:
foreach (KeyValuePair<string, HtmlInputImage> kvp in smartPenImageDictionary)
{
Console.WriteLine("Value " + kvp.Value);
}

A dictionary doesn't have a "beginning" and "end" - it's unordered.
However, you can iterate over the keys or the values:
foreach (string key in smartPenImageDictionary.Keys)
{
...
}
foreach (HtmlInputImage image in smartPenImageDictionary.Values)
{
...
}
or key/value pairs:
foreach (KeyValuePair<string, HtmlInputImage> pair in smartPenImageDictionary)
{
string key = pair.Key;
HtmlInputImage image = pair.Value;
...
}
(Or course var makes the last case rather nicer.)

I assume you want them in order, the same way an IList<T> provides. As far as I know there is no order guaranteed for a Dictionary<Tkey,TValue>, so you'll need to
mydictionary.ToList();
However as you add and remove items, or even call this again it may change. One solution is to write your own Collection that has a custom indexer you can use.

How to iterate over a dictionary?

I've seen a few different ways to iterate over a dictionary in C#. Is there a standard way?

foreach(KeyValuePair<string, string> entry in myDictionary)
{
// do something with entry.Value or entry.Key
}

If you are trying to use a generic Dictionary in C# like you would use an associative array in another language:
foreach(var item in myDictionary)
{
foo(item.Key);
bar(item.Value);
}
Or, if you only need to iterate over the collection of keys, use
foreach(var item in myDictionary.Keys)
{
foo(item);
}
And lastly, if you're only interested in the values:
foreach(var item in myDictionary.Values)
{
foo(item);
}
(Take note that the var keyword is an optional C# 3.0 and above feature, you could also use the exact type of your keys/values here)

In some cases you may need a counter that may be provided by for-loop implementation. For that, LINQ provides ElementAt which enables the following:
for (int index = 0; index < dictionary.Count; index++) {
var item = dictionary.ElementAt(index);
var itemKey = item.Key;
var itemValue = item.Value;
}

Depends on whether you're after the keys or the values...
From the MSDN Dictionary(TKey, TValue) Class description:
// When you use foreach to enumerate dictionary elements,
// the elements are retrieved as KeyValuePair objects.
Console.WriteLine();
foreach( KeyValuePair<string, string> kvp in openWith )
{
Console.WriteLine("Key = {0}, Value = {1}",
kvp.Key, kvp.Value);
}
// To get the values alone, use the Values property.
Dictionary<string, string>.ValueCollection valueColl =
openWith.Values;
// The elements of the ValueCollection are strongly typed
// with the type that was specified for dictionary values.
Console.WriteLine();
foreach( string s in valueColl )
{
Console.WriteLine("Value = {0}", s);
}
// To get the keys alone, use the Keys property.
Dictionary<string, string>.KeyCollection keyColl =
openWith.Keys;
// The elements of the KeyCollection are strongly typed
// with the type that was specified for dictionary keys.
Console.WriteLine();
foreach( string s in keyColl )
{
Console.WriteLine("Key = {0}", s);
}

Generally, asking for "the best way" without a specific context is like asking
what is the best color?
One the one hand, there are many colors and there's no best color. It depends on the need and often on taste, too.
On the other hand, there are many ways to iterate over a Dictionary in C# and there's no best way. It depends on the need and often on taste, too.
Most straightforward way
foreach (var kvp in items)
{
// key is kvp.Key
doStuff(kvp.Value)
}
If you need only the value (allows to call it item, more readable than kvp.Value).
foreach (var item in items.Values)
{
doStuff(item)
}
If you need a specific sort order
Generally, beginners are surprised about order of enumeration of a Dictionary.
LINQ provides a concise syntax that allows to specify order (and many other things), e.g.:
foreach (var kvp in items.OrderBy(kvp => kvp.Key))
{
// key is kvp.Key
doStuff(kvp.Value)
}
Again you might only need the value. LINQ also provides a concise solution to:
iterate directly on the value (allows to call it item, more readable than kvp.Value)
but sorted by the keys
Here it is:
foreach (var item in items.OrderBy(kvp => kvp.Key).Select(kvp => kvp.Value))
{
doStuff(item)
}
There are many more real-world use case you can do from these examples.
If you don't need a specific order, just stick to the "most straightforward way" (see above)!

C# 7.0 introduced Deconstructors and if you are using .NET Core 2.0+ Application, the struct KeyValuePair<> already include a Deconstruct() for you. So you can do:
var dic = new Dictionary<int, string>() { { 1, "One" }, { 2, "Two" }, { 3, "Three" } };
foreach (var (key, value) in dic) {
Console.WriteLine($"Item [{key}] = {value}");
}
//Or
foreach (var (_, value) in dic) {
Console.WriteLine($"Item [NO_ID] = {value}");
}
//Or
foreach ((int key, string value) in dic) {
Console.WriteLine($"Item [{key}] = {value}");
}

I would say foreach is the standard way, though it obviously depends on what you're looking for
foreach(var kvp in my_dictionary) {
...
}
Is that what you're looking for?

You can also try this on big dictionaries for multithreaded processing.
dictionary
.AsParallel()
.ForAll(pair =>
{
// Process pair.Key and pair.Value here
});

I appreciate this question has already had a lot of responses but I wanted to throw in a little research.
Iterating over a dictionary can be rather slow when compared with iterating over something like an array. In my tests an iteration over an array took 0.015003 seconds whereas an iteration over a dictionary (with the same number of elements) took 0.0365073 seconds that's 2.4 times as long! Although I have seen much bigger differences. For comparison a List was somewhere in between at 0.00215043 seconds.
However, that is like comparing apples and oranges. My point is that iterating over dictionaries is slow.
Dictionaries are optimised for lookups, so with that in mind I've created two methods. One simply does a foreach, the other iterates the keys then looks up.
public static string Normal(Dictionary<string, string> dictionary)
{
string value;
int count = 0;
foreach (var kvp in dictionary)
{
value = kvp.Value;
count++;
}
return "Normal";
}
This one loads the keys and iterates over them instead (I did also try pulling the keys into a string[] but the difference was negligible.
public static string Keys(Dictionary<string, string> dictionary)
{
string value;
int count = 0;
foreach (var key in dictionary.Keys)
{
value = dictionary[key];
count++;
}
return "Keys";
}
With this example the normal foreach test took 0.0310062 and the keys version took 0.2205441. Loading all the keys and iterating over all the lookups is clearly a LOT slower!
For a final test I've performed my iteration ten times to see if there are any benefits to using the keys here (by this point I was just curious):
Here's the RunTest method if that helps you visualise what's going on.
private static string RunTest<T>(T dictionary, Func<T, string> function)
{
DateTime start = DateTime.Now;
string name = null;
for (int i = 0; i < 10; i++)
{
name = function(dictionary);
}
DateTime end = DateTime.Now;
var duration = end.Subtract(start);
return string.Format("{0} took {1} seconds", name, duration.TotalSeconds);
}
Here the normal foreach run took 0.2820564 seconds (around ten times longer than a single iteration took - as you'd expect). The iteration over the keys took 2.2249449 seconds.
Edited To Add:
Reading some of the other answers made me question what would happen if I used Dictionary instead of Dictionary. In this example the array took 0.0120024 seconds, the list 0.0185037 seconds and the dictionary 0.0465093 seconds. It's reasonable to expect that the data type makes a difference on how much slower the dictionary is.
What are my Conclusions?
Avoid iterating over a dictionary if you can, they are substantially slower than iterating over an array with the same data in it.
If you do choose to iterate over a dictionary don't try to be too clever, although slower you could do a lot worse than using the standard foreach method.

As already pointed out on this answer, KeyValuePair<TKey, TValue> implements a Deconstruct method starting on .NET Core 2.0, .NET Standard 2.1 and .NET Framework 5.0 (preview).
With this, it's possible to iterate through a dictionary in a KeyValuePair agnostic way:
var dictionary = new Dictionary<int, string>();
// ...
foreach (var (key, value) in dictionary)
{
// ...
}

There are plenty of options. My personal favorite is by KeyValuePair
Dictionary<string, object> myDictionary = new Dictionary<string, object>();
// Populate your dictionary here
foreach (KeyValuePair<string,object> kvp in myDictionary)
{
// Do some interesting things
}
You can also use the Keys and Values Collections

With .NET Framework 4.7 one can use decomposition
var fruits = new Dictionary<string, int>();
...
foreach (var (fruit, number) in fruits)
{
Console.WriteLine(fruit + ": " + number);
}
To make this code work on lower C# versions, add System.ValueTuple NuGet package and write somewhere
public static class MyExtensions
{
public static void Deconstruct<T1, T2>(this KeyValuePair<T1, T2> tuple,
out T1 key, out T2 value)
{
key = tuple.Key;
value = tuple.Value;
}
}

As of C# 7, you can deconstruct objects into variables. I believe this to be the best way to iterate over a dictionary.
Example:
Create an extension method on KeyValuePair<TKey, TVal> that deconstructs it:
public static void Deconstruct<TKey, TVal>(this KeyValuePair<TKey, TVal> pair, out TKey key, out TVal value)
{
key = pair.Key;
value = pair.Value;
}
Iterate over any Dictionary<TKey, TVal> in the following manner
// Dictionary can be of any types, just using 'int' and 'string' as examples.
Dictionary<int, string> dict = new Dictionary<int, string>();
// Deconstructor gets called here.
foreach (var (key, value) in dict)
{
Console.WriteLine($"{key} : {value}");
}

foreach is fastest and if you only iterate over ___.Values, it is also faster

Using C# 7, add this extension method to any project of your solution:
public static class IDictionaryExtensions
{
public static IEnumerable<(TKey, TValue)> Tuples<TKey, TValue>(
this IDictionary<TKey, TValue> dict)
{
foreach (KeyValuePair<TKey, TValue> kvp in dict)
yield return (kvp.Key, kvp.Value);
}
}
And use this simple syntax
foreach (var(id, value) in dict.Tuples())
{
// your code using 'id' and 'value'
}
Or this one, if you prefer
foreach ((string id, object value) in dict.Tuples())
{
// your code using 'id' and 'value'
}
In place of the traditional
foreach (KeyValuePair<string, object> kvp in dict)
{
string id = kvp.Key;
object value = kvp.Value;
// your code using 'id' and 'value'
}
The extension method transforms the KeyValuePair of your IDictionary<TKey, TValue> into a strongly typed tuple, allowing you to use this new comfortable syntax.
It converts -just- the required dictionary entries to tuples, so it does NOT converts the whole dictionary to tuples, so there are no performance concerns related to that.
There is a only minor cost calling the extension method for creating a tuple in comparison with using the KeyValuePair directly, which should NOT be an issue if you are assigning the KeyValuePair's properties Key and Value to new loop variables anyway.
In practice, this new syntax suits very well for most cases, except for low-level ultra-high performance scenarios, where you still have the option to simply not use it on that specific spot.
Check this out: MSDN Blog - New features in C# 7

Simplest form to iterate a dictionary:
foreach(var item in myDictionary)
{
Console.WriteLine(item.Key);
Console.WriteLine(item.Value);
}

I found this method in the documentation for the DictionaryBase class on MSDN:
foreach (DictionaryEntry de in myDictionary)
{
//Do some stuff with de.Value or de.Key
}
This was the only one I was able to get functioning correctly in a class that inherited from the DictionaryBase.

Sometimes if you only needs the values to be enumerated, use the dictionary's value collection:
foreach(var value in dictionary.Values)
{
// do something with entry.Value only
}
Reported by this post which states it is the fastest method:
http://alexpinsker.blogspot.hk/2010/02/c-fastest-way-to-iterate-over.html

I know this is a very old question, but I created some extension methods that might be useful:
public static void ForEach<T, U>(this Dictionary<T, U> d, Action<KeyValuePair<T, U>> a)
{
foreach (KeyValuePair<T, U> p in d) { a(p); }
}
public static void ForEach<T, U>(this Dictionary<T, U>.KeyCollection k, Action<T> a)
{
foreach (T t in k) { a(t); }
}
public static void ForEach<T, U>(this Dictionary<T, U>.ValueCollection v, Action<U> a)
{
foreach (U u in v) { a(u); }
}
This way I can write code like this:
myDictionary.ForEach(pair => Console.Write($"key: {pair.Key}, value: {pair.Value}"));
myDictionary.Keys.ForEach(key => Console.Write(key););
myDictionary.Values.ForEach(value => Console.Write(value););

If you want to use a for loop, you can do as below:
var keyList=new List<string>(dictionary.Keys);
for (int i = 0; i < keyList.Count; i++)
{
var key= keyList[i];
var value = dictionary[key];
}

I will take the advantage of .NET 4.0+ and provide an updated answer to the originally accepted one:
foreach(var entry in MyDic)
{
// do something with entry.Value or entry.Key
}

If say, you want to iterate over the values collection by default, I believe you can implement IEnumerable<>, Where T is the type of the values object in the dictionary, and "this" is a Dictionary.
public new IEnumerator<T> GetEnumerator()
{
return this.Values.GetEnumerator();
}

The standard way to iterate over a Dictionary, according to official documentation on MSDN is:
foreach (DictionaryEntry entry in myDictionary)
{
//Read entry.Key and entry.Value here
}

I wrote an extension to loop over a dictionary.
public static class DictionaryExtension
{
public static void ForEach<T1, T2>(this Dictionary<T1, T2> dictionary, Action<T1, T2> action) {
foreach(KeyValuePair<T1, T2> keyValue in dictionary) {
action(keyValue.Key, keyValue.Value);
}
}
}
Then you can call
myDictionary.ForEach((x,y) => Console.WriteLine(x + " - " + y));

Dictionary< TKey, TValue > It is a generic collection class in c# and it stores the data in the key value format.Key must be unique and it can not be null whereas value can be duplicate and null.As each item in the dictionary is treated as KeyValuePair< TKey, TValue > structure representing a key and its value. and hence we should take the element type KeyValuePair< TKey, TValue> during the iteration of element.Below is the example.
Dictionary<int, string> dict = new Dictionary<int, string>();
dict.Add(1,"One");
dict.Add(2,"Two");
dict.Add(3,"Three");
foreach (KeyValuePair<int, string> item in dict)
{
Console.WriteLine("Key: {0}, Value: {1}", item.Key, item.Value);
}

The best answer is of course: Think, if you could use a more appropriate data structure than a dictionary if you plan to iterate over it- as Vikas Gupta mentioned already in the (beginning of the) discussion under the question. But that discussion as this whole thread still lacks surprisingly good alternatives. One is:
SortedList<string, string> x = new SortedList<string, string>();
x.Add("key1", "value1");
x.Add("key2", "value2");
x["key3"] = "value3";
foreach( KeyValuePair<string, string> kvPair in x )
Console.WriteLine($"{kvPair.Key}, {kvPair.Value}");
Why it could be argued a code smell of iterating over a dictionary (e.g. by foreach(KeyValuePair<,>) ?
A basic principle of Clean Coding:
"Express intent!"
Robert C. Martin writes in "Clean Code": "Choosing names that reveal intent". Obviously naming alone is too weak. "Express (reveal) intent with every coding decision" expresses it better.
A related principle is "Principle of least surprise" (=Principle of Least Astonishment).
Why this is related to iterating over a dictionary? Choosing a dictionary expresses the intent of choosing a data structure which was made for primarily finding data by key. Nowadays there are so much alternatives in .NET, if you want to iterate through key/value pairs that you could choose something else.
Moreover: If you iterate over something, you have to reveal something about how the items are (to be) ordered and expected to be ordered!
Although the known implementations of Dictionary sort the key collection in the order of the items added-
AFAIK, Dictionary has no assured specification about ordering (has it?).
But what are the alternatives?
TLDR:
SortedList: If your collection is not getting too large, a simple solution would be to use SortedList<,> which gives you also full indexing of key/value pairs.
Microsoft has a long article about mentioning and explaining fitting collections:
Keyed collection
To mention the most important: KeyedCollection<,> and SortedDictionary<,> .
SortedDictionary<,> is a bit faster than SortedList for only inserting if it gets large, but lacks indexing and is needed only if O(log n) for inserting is preferenced over other operations. If you really need O(1) for inserting and accept slower iterating in exchange, you have to stay with simple Dictionary<,>.
Obviously there is no data structure which is the fastest for every possible operation..
Additionally there is ImmutableSortedDictionary<,>.
And if one data structure is not exactly what you need, then derivate from Dictionary<,> or even from the new ConcurrentDictionary<,> and add explicit iteration/sorting functions!

var dictionary = new Dictionary<string, int>
{
{ "Key", 12 }
};
var aggregateObjectCollection = dictionary.Select(
entry => new AggregateObject(entry.Key, entry.Value));

Just wanted to add my 2 cent, as the most answers relate to foreach-loop.
Please, take a look at the following code:
Dictionary<String, Double> myProductPrices = new Dictionary<String, Double>();
//Add some entries to the dictionary
myProductPrices.ToList().ForEach(kvP =>
{
kvP.Value *= 1.15;
Console.Writeline(String.Format("Product '{0}' has a new price: {1} $", kvp.Key, kvP.Value));
});
Altought this adds a additional call of '.ToList()', there might be a slight performance-improvement (as pointed out here foreach vs someList.Foreach(){}),
espacially when working with large Dictionaries and running in parallel is no option / won't have an effect at all.
Also, please note that you wont be able to assign values to the 'Value' property inside a foreach-loop. On the other hand, you will be able to manipulate the 'Key' as well, possibly getting you into trouble at runtime.
When you just want to "read" Keys and Values, you might also use IEnumerable.Select().
var newProductPrices = myProductPrices.Select(kvp => new { Name = kvp.Key, Price = kvp.Value * 1.15 } );

in addition to the highest ranking posts where there is a discussion between using
foreach(KeyValuePair<string, string> entry in myDictionary)
{
// do something with entry.Value or entry.Key
}
or
foreach(var entry in myDictionary)
{
// do something with entry.Value or entry.Key
}
most complete is the following because you can see the dictionary type from the initialization, kvp is KeyValuePair
var myDictionary = new Dictionary<string, string>(x);//fill dictionary with x
foreach(var kvp in myDictionary)//iterate over dictionary
{
// do something with kvp.Value or kvp.Key
}