linq投影元素计数

Question

假设:

var a = SomeCollection.OrderBy(...)
              .Select(f => new MyType
                               {
                                  counter = ? //I want counter value, so what first
                                              //object have counter=1, second counter=2 
                                              //and so on
                                  a=f.sometthing,
                                  ...
                                });

如何设置此计数器值？或者我喜欢a后来迭代？

Answer 1

使用Select的重载,它可以为您提供当前元素的从0开始的索引.

.Select((item, index) => new MyType
            { 
                counter = index + 1,
                a = item.Something