Can we get key by passing value from dictionary in c# . without loopin

Question

Can we get key by passing value from dictionary in c# . without looping

Rajanikant Hawaldar · Answer

Have you used first or default with lambda function? Something like this dctName.FirstorDefault(i=>I.value==valuepassed).Key

Sachin Singh · Answer

please , please explain the scenario where you need key according to value? keys are unique and value can be duplicate for example Dictionary dic = new Dictionary (); dic.Add( "key1" , "Ram" ); dic.Add( "key2" , "Ram" ); as you can see the values are same but keys are different , There are mainly 3 types of generic collection Index based:- List and array list Key based:- Dictionary and LookUp priority based:- Stack and Queue So the purpose of dictionary is to find value based on key,so, in which scenario you want key from value becomes important. if values are unique dic.FirstorDefault(x=>x.Value== "myValue" ).Key ; if values are duplicate Dictionary dic = new Dictionary (); dic.Add( "key1" , "Ram" ); dic.Add( "key2" , "Ram" ); var keys = dic.Where(x => x.Value == "myvalue" ).Select(x => x.Key);

Jignesh Kumar · Answer

Hi Manoj, Please use this one to get key name by Value in dictionery. Dictionary string , string > dic = new Dictionary string , string >(); dic.Add( "1" , "one" ); dic.Add( "2" , "two" ); dic.Add( "3" , "three" ); dic.Add( "4" , "four" ); dic.Add( "5" , "five" ); string myValues = "five" ; var requestedKey = dic.FirstOrDefault(x => x.Value == myValues).Key;