C# list to dictionary key value

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August undefined, 2024

WebJun 27, 2011 · Of course you can use a dictionary as a sequence of key/value pairs, so you could have: var keysForValues = dictionary.Where (pair => values.Contains (pair.Value)) .Select (pair => pair.Key); Just be aware this will be an O (n) operation, even if your "values" is a HashSet or something similar (with an efficient containment check). WebSep 8, 2016 · First you have to get the key and value using the select-overload that also provices the index of the currently used element: var tmp = sList.Select ( (x, i) => new { Key = i, Value = x }); Now create the dictionary: var result = tmp.ToDictionary (x => x.Key, x => x.Value); Or as a one-liner:

c# - Dictionary with two keys? - Stack Overflow

http://www.dedeyun.com/it/csharp/98761.html WebJun 30, 2024 · A more complete answer would be to not assume Key type being a string. var keyList = yourDictionary.Keys.ToList(); Or if you want to go nuts and not use var or … greenwood learning alliance

Python – Convert list to Single Dictionary Key Value list

WebMar 31, 2024 · A Computer Science portal for geeks. It contains well written, well thought and well explained computer science and programming articles, quizzes and practice/competitive programming/company interview Questions. WebNov 8, 2013 · I am trying to bind a dictionary's key to a row of the grid in a listbox, and bind the dictionary's value to another row of the grid. key's type is Book, a class thati wrote and the value's type is int. i want to write the elements of the class and the integer value in grid. Can you help me on this? WebDisable compiler optimisation for a specific function or block of code (C#) Check if list contains element that contains a string and get that element in C#; ... In C#, you can get … foam play mat tiles outdoor suppliers

c# - How to get dictionary values as a generic list - Stack Overflow

How to Convert KeyValuePair to Dictionary in C# - Stack Overflow

WebI have a dictionary of lists and was wondering if there was a good way of obtaining all the common values. 我有一个列表字典，想知道是否有一种很好的方法来获取所有通用值。 … Webcsharp// Assuming you have a dictionary with a list of values var dict = new Dictionary> { { "key1", new List { 1, 2, 3 } }, { "key2", new List { 4, 5 } }, { "key3", new List { 6 } } }; // Convert the dictionary to an IEnumerable of tuples var enumerable = dict.SelectMany(kv => kv.Value.Select(v => (kv.Key, v))); // Use the IEnumerable as needed … greenwood lawn mower \u0026 chainsaw centreWeb2 days ago · It should be noted that your GetServices method creates a new copy of the values of the _dictionary each time it is called, so the lists created by your code are not shared between threads, and so you wouldn't have any problems even if the ImmutableList class was not thread-safe. greenwood learning alliance virtual college

"WebUse two dictionaries, one for value-to-key mapping and one for key-to-value mapping (which would take up twice as much space in memory). Use Method 1 if … " - C# list to dictionary key value

C# list to dictionary key value

How to add multiple values to Dictionary in C#? - iditect.com

WebMar 7, 2024 · Key: A --> Value: {1,2,3} Key: B --> Value: {a,b,c} Key: C --> Value: {Hi,Hello,Hola} I would like to create a .csv file with Headers corresponding to my dictionary Keys, and 'Columns' corresponding to the List's. WebAug 29, 2012 · Just use the key name on the dictionary. C# has this: Dictionary dict = new Dictionary (); dict.Add ("UserID", "test"); string userIDFromDictionaryByKey = dict ["UserID"]; If you look at the tip suggestion: Share Improve this answer Follow edited Nov 8, 2024 at 4:15 Peter Mortensen 31k 21 105 126

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WeborignalDictionary.ToDictionary (kp => kp.Value, kp => kp.Key); This works because IDictionary; is also an IEnumerable> … WebJul 15, 2015 · // #1: get all keys (remove Distinct () if you don't want it) List allKeys = (from kvp in KV_List select kvp.Key).Distinct ().ToList (); // allKeys = { "qwer", "zxcv", "hjkl" } // #2: get values for a key string key = "qwer"; List values = (from kvp in KV_List where kvp.Key == key select kvp.Value).ToList (); // values = { "asdf", "ghjk" } // #3: …

WebSep 22, 2013 · ToDictionary does exist in C# (edit: not the same ToDictionary you were thinking of) and can be used like this: var list = new List> {kvp}; var dictionary = list.ToDictionary (x => x.Key, x => x.Value); Here list could be a … WebDec 16, 2014 · The List instance acting as a key is referentially unequal to the instance referred to by searchObject. If you want the dictionary to use the values in the …

WebIn this example, we define an array of KeyValuePair objects, each containing a key-value pair to add to the dictionary. We then pass this array to the Dictionary …

WebJan 23, 2014 · You could construct a list of SelectListItem objects from the Dictionary and then create a SelectList from that. var dict = new Dictionary { {"a1", "Car"}, …

Webcsharpvar items = new[] { new KeyValuePair ("a", 1), new KeyValuePair ("b", 2), new KeyValuePair ("c", 3) }; var dictionary = new Dictionary (items); In this example, we define an array of KeyValuePair objects, each containing a key-value pair to add to the dictionary. greenwood landscaping wichita falls txWebMar 13, 2015 · Well, when you group you can specify the value you want for each element of the group: var dictionary = list.GroupBy(p => p.TypeID, p => p.NoticeID) … green woodlands foundationWebDec 26, 2014 · C# var res = list.ToDictionary (x => x, x => x); The first lambda lets you pick the key, the second one picks the value. You can play with it and make values differ from the keys, like this: C# var res = list.ToDictionary (x => x, x => string .Format ( "Val: {0}", x)); If your list contains duplicates, add Distinct () like this: C# greenwood la to ratcliff vet shreveportWeb2 days ago · By this step, the value is in the format like: {string [3]}: "Type1","good","this" {string [3]}: "Type2","bad","that" {string [3]}: "Type1","normal","those" Now I want to use linq to convert it to a Dictionary. The value in the list should be the third value in the each string array. greenwood landmark theatreWebFeb 27, 2012 · CreateSetComparer allows the dictionary to use the values of the set for equality testing. List duelSource = GetDuels (); Dictionary, Duel> duels = new Dictionary, Duel> (HashSet.CreateSetComparer ()); foreach (Duel d in duelSource) { duels.Add (d.GetUserSet (), d); } And finding a duel: greenwood leather australiaWebMay 1, 2012 · The ToDictionary () extension method allows you to specify which parts of your list item you want for a key and value, including the key/value of KeyValuePair<> list item. var dictionary = list.ToDictionary ( (keyItem) => keyItem.Key, (valueItem) => valueItem.Value); foam play mat tiles factoryWebAug 31, 2010 · The ToDictionary () method has an overload that takes two lambda expressions (nitpick: delegates); one for the key and one for the value. For example: var … greenwood leadership academy tulsa oklahoma