How to Convert Array to String[] in C#

Question

string[] B = C.OfType<object>().Where(o =>o  != null).Select(o => o.ToString()).ToArray();

我尝试将数组C转换为string[]但是数组C有很多null ，我希望将null更改为" "我该怎么办？

Answer 1

You don't need OfType<object>() , simply call string.Concat :

var s = string.Concat(C.ToArray());

If you look at documentation:

The method concatenates each object in args by calling the parameterless ToString method of that object; it does not add any delimiters. String.Empty is used in place of any null object in the array.'

Answer 2

This should work:

var B = C.OfType<string>().Select(o => o ?? " ").ToArray();

.OfType<string>() will filter out all non-string values from C.

.Select(o => o ?? " ") will select the value, or " " if the value was null.

and .ToArray() will take the IEnumerable and turn it into a string[] .