Selecting items from generic list based on true condition from another list
c#, lambda, linq
Solution
var results = listData.Where((item, index) => listFilter[index] == 1);
Note that this will fail if listData is longer than listFilter, same as your code.
Problem
I am wondering if there would be any LINQ/Lambda expression solution for the problem below. I have 2 generic lists List 1 ``` public class Data { public string ID { get; set;} public string Package { get; set;} } List<Data> listData = new List<Data>(); Data data1 = new Data { ID = "1", Package = "Test" }; Data data2 = new Data { ID = "2", Package = "Test2" }; Data data3 = new Data { ID = "3", Package = "Test2" }; Data data4 = new Data { ID = "4", Package = "Test4" }; listData.Add(data1); listData.Add(data2); listData.Add(data3); listData.Add(data4); ``` List 2 ``` List<int> listFilter = List<int>(); listFilter.Add(1); listFilter.Add(0); listFilter.Add(0); listFilter.Add(1); ``` I would like to filter "listData" based on the true (1) criteria from "listFilter". For the above example, I must be able to pull data1 and data4 into a new list. At the moment, I am using a for loop to achieve this as below. ``` List<Data> listResult = new List<Data>(); for(int index=0; index<listData.Count; index++) { if(listFilter[index]==1) { listResult.Add(listData[index]); } } ``` I would appreciate if someone could show me to use LINQ or Lambda expression to achieve this. Thanks Balan