MapIndexed3

Builds a new collection whose elements are the results of applying the given mapping function to each triples of the elements of the collections.

The integer index passed to the function indicates the index (from 0) of element being transformed.

Parameters	Returns
Func<int, T, T2, T3, TResult> mapping IEnumerable<T> source IEnumerable<T2> source2 IEnumerable<T3> source3	IEnumerable<TResult>

Usage

Concatenating values and its index from three collections

//IEnumerable<int> source = { 1, 2, 3, 4, 5 }
//IEnumerable<int> source2 = { 5, 3, 3, 3, 0 }
//IEnumerable<string> source3 = {"Value", "Val", "V" }

IEnumerable<string> result = 
    source.Map3(
        source2,
        source3, 
        (index, value1, value2, value3) => 
            $"{value3} {index}: {value1 + value2}");

//result = { "Value 0: 6", "Val 1: 5", "V 2: 6" }