how to set value in list using linq c#

I am having a datatable having Id, System and Date. Create and initialize a list of integer types. class XMLTransform { static void Main () { // Create the data source by using a collection initializer. 1 2 3 4 var query = from x in employeeList join y in departmentList on x.code equals y.Code select new { x, y }; And then apply the foreach loop on that linq as below, 1 2 foreach(var match in query) Instead of parentheses, use curly braces after the list’s type. var validCustomers = customers.Where(c => c.IsValid); foreach( Customer cust in validCustomers) { cust.CreditLimit = 1000; } Getting to One Line of Code If you're willing to use the ToList method to convert the collection into a List, you can get an even terser statement by using the List object's ForEach method. Notify me of new posts by email. Name *. listEmployees = listEmployees.Select(c => { c.EmpName = c.EmpName.Replace("Raj", "Admin"); return c; }).ToList< Employee >(); Above code returns a list of Employees by replacing employee name “Raj” with “Admin” and returns all properties including EmpId. Linq Range Method in C#: This method is used to Generates a sequence of integral (integer) numbers within a specified range. To solve this we can first get the both lists objects which are validating our condition using linq. Apple, Large Fruit Details After Update. Here's a summary of the situation and I will provide full sample code below: I have a list of objects where 2 properties are: Why Join Become a member Login C# Corner. Function finds all listed properties in the object and then sets their values. int start) specifies the value of … Accept Solution Reject Solution. It can be done this way as well foreach (Company company in listofCompany.Where(d => d.Id = 1)).ToList()) You also learned how to chain methods together, and you used this technique to add a primary sort OrderBy () and a secondary sort ThenBy () to a filtered list. Apple, Small Fruit Details Before Update. Be aware that it only updates the first company it found with company id 1. For multiple (from c in listOfCompany where c.id == 1 select c).First(... c# update certain items in a list linq. public class Company { public int id { get; set; } public int Name { get; set; } } List listofCompany = new List (); this is my collection of company list I want to assign values to Name property using LINQ. c# foreach + update full object. You can use Magiq, a batch operation framework for LINQ. The following function accepts an object and a collection of name/value pairs, each pair representing one property returning integer value. In my previous article, I have explained few ways to convert list into datatable using C#, now in this article, I will explain various ways to convert datatable into List using C# in ASP.NET.. update a list row in linq c#. At the end of this article, you will understand the following the Linq Distinct Query in details with the following pointers. The code which includes LINQ query is easier to write and more readable than the code based on loops. Below programs illustrate the … ACCEPTED ANSWER. The following is the signature of this method. How can we update the values of a collection using LINQ in C#? If the collection is a List, then we can make use of ForEach extension method which is available as part of LINQ. Fruit Details Before Update. In this blog, i'll explain that how can we update multiple values in list. UPDATE This can be simplified to be... listOf... LinqToSql.cs 2. In this tutorial, you learned how to filter a C# collection using a LINQ query. This method operates on a single data source. Select in LINQ Example: LINQ Select in C# Syntax Select query in LINQ Select method is used to select one or more items from collection or list object, here we see some example of linq select statement . The first parameter (i.e. C# Linq ForEach Where – Execute an action foreach item in a collect where a condition is true The example above will perform the WriteLine method on every item in a list. Sometimes though, you only want to perform such an action on certain items. This is easy to do by using a where clause to filter the items, before using foreach. I want to check All the list of values FromList into ToList1 and ToList2. LINQ is for querying, not for updating the data. Use LINQ to get the items that you want to modify, and then modify them in a foreach loop: Demo. Show activity on this post. Show activity on this post. Select (), like any other LINQ method, doesn't change a source collection, instead, it return a new collection. If you only need some target columns' value from the selected rows (for example, we only need "Id" and "Name" columns' value), you can create a new anonymous type of enumerable to bind the data. linqu update in list. listofCompany.Where (d => d.Id = 1); (I want to assing name property of company id 1) The following example transforms objects in an in-memory data structure into XML elements. Create and initialize a list of integer types. LINQ query to get specific column values from a DataTable in C#. You can create a extension method: public static IEnumerable Do(this IEnumerable self, Action action) { For example, let us consider a List> which needs to be converted to List. How can we update the values of a collection using LINQ in C#? If the collection is a List, then we can make use of ForEach extension method which is available as part of LINQ. Fruit Details Before Update. So there is nothing Linq about this method or syntax, it … Use Linq and apply lambda expression as shown below to achieve this. var query = from record in records join key in Keys on record.key equals key select record; In case you can have multiple keys for the same record, you can use the Distinct operation. Save my name, email, and website in this browser for the next time I comment. The parameter T is the type of elements in the list. We can also user First instead of FirstOrDefault.We can write the above code like this. Approach: 1. In the opened "Add New Item" dialog make sure Windows Form is selected and then rename the "Form1.cs" to "LinqToXml". There Contains method in C# is implemented in two different namespaces as shown in the below image. Suppose here is the our class Object. In this blog, i'll explain that how can we update multiple values in list. Console.WriteLine ("ID : " + farmer.ID + " Name : " + farmer.Name + "Income : " + farmer.Income); Ensure that your M:M, 1:M, and M:1 relationships are kept in synch * as you perform these adds/updates/deletes. In LINQ, the ToDictionary operator is useful to convert list/collection (IEnumerable) items to a new dictionary object (Dictionary), and it will optimize the list/collection items by getting only required values. customers.Where(c => c.IsValid).SetValue(c => c.CreditLimit = 1000).ToList(); Or like this: var newCustomers = customers.Where(c => c.IsValid).SetValue(c => c.CreditLimit = 1000); Or like this for Entity Framework: db.Customers.Where(c => c.IsValid).ToList().SetValue(c => c.CreditLimit = … var validCustomers = customers.Where(c => c.IsValid); foreach( Customer cust in validCustomers) { cust.CreditLimit = 1000; } Getting to One Line of Code If you're willing to use the ToList method to convert the collection into a List, you can get an even terser statement by using the List object's ForEach method. You can also consider this method, merge them, and then group them to determine whether there is false in each group: public static void Main() {. Specifically, you learned how to use the Where () query to filter a List according to specified parameters. For example nums. The SelectMany in LINQ is used to project each element of a sequence to an IEnumerable and then flatten the resulting sequences into one sequence. Display the result using the foreach loop. Find the distinct values from one property: group a list of Product objects with Id property, and pick a winner out of the group. You can create a extension method: public static IEnumerable Do(this IEnumerable self, Action action) { Example 1: linq to update a list customers.Where(c => c.IsValid).Select(c => { c.CreditLimit = 1000; return c; }).ToList(); Example 2: linq to update a list var newC Menu NEWBEDEV Python Javascript Linux Cheat sheet Operator. Use Linq and apply lambda expression as shown below to achieve this. You also learned how to chain methods together, and you used this technique to add a primary sort OrderBy () and a secondary sort ThenBy () to a filtered list. { new A() { Index = 1, State = false }, new A() { Index = 2, State = false }, new A() { Index = 3, State = true }, Using LINQ to update/change values in collection lambda C# select any perform action list call function c# list keyvaluepair update value All and Any linq c# examlpe replace linq from list c# edit list element linq c# update value in list c# C# select keyword lambda c# linq select as new object set field in list linq switch with lambda c# Refer below code. LINQ query to get specific column values from a DataTable in C#. How to flatten a list using LINQ C#? foreach(var item in self) {... Orange, Small Fruit Details After Update. Orange, Large. For example nums. In this blog we will see how LINQ query result can be converted into list and later how the list can be consumed according to the any requirement perspective. Be aware that it only updates the first company it found with company id 1. For multiple (from c in listOfCompany where c.id == 1 select c).First(... Apple, Small Fruit Details Before Update. So now shall we see how to use the multiple where clause in a linq and lambda query. It can be done this way as well foreach (Company company in listofCompany.Where(d => d.Id = 1)).ToList()) To do this, you should use a plain old for loop: List list = new List(); list.Add(1); list.Add(2); list.Add(3); for (int i = 0; i < list.Count; ++i) { list[i] = list[i] + 6; } There is no reason to use LINQ just for the sake of it to do this. In this article. List vendlist = new List(); var vnlist = from up in spcall where up.Caption == "Contacted" select new { up.Caption, up.TargetDate, up.ActualDate, up.Value }; foreach (var item in vnlist) { CheckItems temp = new CheckItems(); temp.Description = item.Caption; temp.TargetDate = string.Format("{0:MM/dd/yyyy}", item.TargetDate); … Here, we're selecting the entire employee set, defining the set variable as , and selecting it, that is, returning the value for the query. We always begin our LINQ statements with from - this defines the set we're working with and the variable we'll use for our set operations. 1 2 3 4 var query = from x in employeeList join y in departmentList on x.code equals y.Code select new { x, y }; And then apply the foreach loop on that linq as below, 1 2 foreach(var match in query) (from user in userlist. The value can be null for reference types. foreach (var student in myList.Where(r => r.Name == "Tom")) { student.Marks = 35; } using System.Linq; It’s worth bearing in mind that the result of A.Except(B) will be an IEnumerable, if you want the result as a list call .ToList() as I’ve done above. Finally these two columns and values check in my table which needs to returns true/False. Distinct. Here - OrganizationList is an array. The purpose of this second article is to continue introducing LINQ to SQL by showing how to: Add/Update/Delete data in your database through your classes using LINQ to SQL. Be aware that it only updates the first company it found with company id 1. For multiple (from c in listOfCompany where c.id == 1 select c).First(... It can be done this way as well foreach (Company company in listofCompany.Where(d => d.Id = 1)).ToList()) //LINQ var objtochange = (from obj in oList where obj.ID == 6 select obj).First(); objtochange = newmyObject; //FindIndex way int indextoChange = oList.FindIndex(delegate(myObject obj) { if (obj.ID == 6) return true; else return false; }); oList[indextoChange] = newmyObject; Not Applicable. Initialize and add items in List // List initialization and adding elements to the end of the list: List< char > lst = new List< char > { 'a', 'b', 'c' }; Create blank list and add items in List using List.Add () You also learned how to chain methods together, and you used this technique to add a primary sort OrderBy () and a secondary sort ThenBy () to a filtered list. Please help how to get this using LINQ. Please read our previous article where we discussed the basics of LINQ Set Operators. 1. Finally these two columns and values check in my table which needs to returns true/False. update list using linq c#. The following code will print out one line for each element in a list using Linq like syntax: var numbers = new List() { 1, 2, 3 }; numbers.ForEach(x => Console.WriteLine(x)); /* this code outputs: 1 2 3 */ Note though, that this is a List extension method in the same System.Collections.Generic as List itself. We select one particular field called "Name" from above list Country object list. For that I have created a class and list with dummy values as shown below. Instead of parentheses, use curly braces after the list’s type. Example of Select in LINQ We select one particular field called "Name" from above list Country object list IList countryList = GetCountryList (); var countryNames = countryList.Where (c => c.Language=="English").Select (s => s.Name); Ensure that your M:M, 1:M, and M:1 relationships are kept in synch * as you perform these adds/updates/deletes. For example nums. user.Phone="1242341237"; user.Address="Some Address"; }); … You can create a extension method: public static IEnumerable Do(this IEnumerable self, Action action) { It provides a solution for the problem of object-relational mapping, and simplifies the interaction between objects and data sources. In this tutorial, you learned how to filter a C# collection using a LINQ query. If the collection is a List, then we can make use of ForEach extension method which is available as part of LINQ. //Extracting the values based on id values present in ids list. Specifically, you learned how to use the Where () query to filter a List according to specified parameters. {. Fruit Details Before Update. To do this, you should use a plain old for loop: List list = new List(); list.Add(1); list.Add(2); list.Add(3); for (int i = 0; i < list.Count; ++i) { list[i] = list[i] + 6; } There is no reason to use LINQ just for the sake of it to do this. Function finds all listed properties in the object and then sets their values. LINQ query to get specific column values from a DataTable in C#. Sub2 value ==> is available in ToList2. This query syntax supports VB.Net, and in C#, it is available in Queryable and Enumerable classes. Return Value: This method returns True if the item is found in the List otherwise returns False. Use the new operator and declare the element type in the angle brackets < >. public class Company { public int id { get; set; } public int Name { get; set; } } List listofCompany = new List (); this is my collection of company list I want to assign values to Name property using LINQ. var result_set = nums.OrderBy (num => num); 3. Add elements in List collection. Click "Add". The following piece of code selects all read/write properties of integer type and converts them to name/value pairs. You can use Magiq, a batch operation framework for LINQ. At the end of this article, you will understand the following the Linq Distinct Query in details with the following pointers. In C#, a list is a generic data structure that can hold any type. But LINQ makes it easy to filter the type members according to various criteria. How to Get the Maximum value from a List of String using LINQ in C# ? Syntax: public bool Contains (T item); Here, item is the object which is to be locate in the List. using Linq would be: listOfCompany.Where(c=> c.id == 1).FirstOrDefault().Name = "Whatever Name"; For example, if you have an ArrayList of Student objects, your from clause should look like this: C#. Note that this can ONLY be used at the time of construction. Website. Create and initialize a list of integer types. public class Company { public int id { get; set; } public int Name { get; set; } } List listofCompany = new List (); this is my collection of company list I want to assign values to Name property using LINQ. Find the distinct values from multiple properties: group a list of Product objects with Id and Price properties, and select the unique item from the group. update object list value in c# linq; c# update value in list using linq; linq update list<()> where; database linq update item in list; how to update list object with linq in c#; linqu how to update all items in list; linq update item list value; update change list item element linq; best way to update a list of objects c# linq; how to update element in list using linq in c# 10 TIPs - To Become a Good Developer/Programmer. The SelectMany in LINQ is used to project each element of a sequence to an IEnumerable and then flatten the resulting sequences into one sequence. c# linq change item in list. You should iterate your list, and modify your values like: foreach (var student in myList) { if (student.Name == "Tom") { student.Marks = 35; } } Or. If the logic to find the maximum value is based on the length of string in the column , below is the sample code do it. c# foreach + update full object.