List Operation In C#

    This Blog  Use For Major operation of List<> in C#
   Introduction
     Lists are considered generics and constructed types. You need to use < and > in the List declaration.
     List <>  is Following Step
1)    Create Class for List

public class AddROSublet     {         string _Id;         string _FaultId;         string _VendorName;         string _VendorId;                      public string VendorName         {             get             {                 return _VendorName;             }             set             {                 _VendorName = value;                             }         }         public string VendorId         {             get             {                 return _VendorId;             }             set             {                 _VendorId = value;            }         }             }

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2) Create object For List and Add Value in List

public List<Test> lParts = new List<Test>(); lParts.Add(new Test() {        Id = 1,     FId = “9999”,     Name =”Tejas”,     vId = 1003     }); lParts.Add(new Test() {        Id = “2”,     FId = “9999”,     Name =”Dhaval”,     vId = 1002     }); lParts.Add(new Test() {        Id = “3”,     FId = “9999”,     Name =”Amit”,     vId = 1001

});

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3)List Operation Related SpecificId one column,ordr by,Gorup by

///This Code  Give All Record for Spcific ID var names1 = lParts.Where(n => n. vId == "1003").ToList(); ///This Code  Give only one value of Column var names1 = lParts.Where(n => n. vId == "1003") .Select(n => n.VendorId).ToList(); /// This Code  Give only one value of Column in one range ex(1,0,0,3) var names2 = lParts.Where(n => n. vId == "1003") .SelectMany(n => n.VendorId).ToList(); ///This Code For Group by and order by var groupedList = lParts.GroupBy(c => new { c.Name, c.VendorId }) .OrderBy(g => g.Key.Name).ThenBy(g => g.Key.VendorId).ToList(); ///This For Group by var groupedList1 = lParts.GroupBy(c => new { c.Name, c.VendorId }) .ToList(); //This Code for order by var groupedList2 = lParts.OrderBy(g => g.Name).ToList(); //This code for Sum var sums = lParts.Sum(x => Convert.ToInt64(x.Id));

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4) List Operation Related Find Index

//Method 1 for find index int index = lParts.FindIndex(lparts => lparts.Id.Equals(Convert.ToString(“12345”),  StringComparison.Ordinal)); //Method 2 for find index int index = lParts.FindIndex( delegate(Test sublet) {     return sublet.Id == Convert.ToString(“12345”); }); int indexChild = lPartsChild.FindIndex( delegate(Test sublet) {     return sublet.Id == Convert.ToString(“12345”); }); //Method 3 for find index int index = lParts.FindIndex( delegate(Test sublet) {     return sublet.Id.Equals(“12345”, StringComparison.Ordinal); }); //This Methos Find and then give last index int firstIndex = lTest.FindIndex(FindTest); //This Methos Find and then give last index int lastIndex = lTest.FindLastIndex(FindTest); //region Index of first in the second half of the collection int mid = lTest.Count / 2; int halfIndex = lTest.FindIndex(mid, mid, FindTest); #endregion //region Index of last in the second half of the collection int halfLastIndex = lTest.FindLastIndex(lTest.Count - 1, mid, FindTest); // Explicit predicate delegate. private static bool FindTest(Test tst) {     if (tst.MainId ==  Textbox1.Text)         return true;     else         return false; }

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5) List Operation Related to Find Operation

//Search and Update value by index value int indexVA = -1; indexVA = lParts.FindIndex(lparts => Convert.ToString(lparts.FName).ToLower() == Convert.ToString(“tejas”); if (indexVA >= 0) {     //lTest[indexVA].Id = 1;     //lTest[indexVA].FName = txtSearch.Text;     lParts [indexVA]. FId = 100;     this.viewMain.ItemsSource = null;     this.viewMain.ItemsSource = lTest;     this.viewMain.SelectedIndex = indexVA; } //Find First Record only Test objTest = lTest.Find( delegate(Test objT) { return objT.FId == Textbox1.Text; } ); ///This For find only first record from list var item = lParts.FirstOrDefault(x => x. vId == "1003"); ///This for find only single record from list var item1 = lParts.SingleOrDefault(x => x.FId == "9999"); //Find Last Record only Test objLastTest = lTest.FindLast( delegate(Test objT) { return objT. FId ==  Textbox1.Text; } ); //Find All Record only lTest = lTest.FindAll( delegate(Test objT) { return objT. FId ==  Textbox1.Text; } ); //This code for give range of array Test[] output = lTest.GetRange(2, 3).ToArray();

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      6)List Operation Related Remove Operation

#region Remove from list lTest.Remove(lTest.Find(delegate(Test objT)         {             return Convert.ToString(objT.Name).ToLower() == “tejas”;         })); #region Remove All from list if (Convert.ToString(txtRemove.Text) != "") {     lTest.RemoveAll(delegate(Test objT)     {         return Convert.ToString(objT.FName).ToLower() == Convert.ToString(“tejas”).ToLower();     }); } #region Remove from index int indx = lTest.FindIndex(ltest => Convert.ToString(ltest.FName).ToLower() == “tejas”); if (indx >= 0)     lTest.RemoveAt(indx); #endregion // Remove from range of class if (indx >= 0)     lTest.RemoveRange(indx, 3); // This Code For Reverse List lTest.Reverse();

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This Very useful in WPF