c# - String Join not working fine -

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following code returns true, why?

var inputs = new object[]{null, 1}; var output = string.join(",", inputs); console.writeline(output == "");//prints true

> output = ""

but following code working fine

var inputs = new object[]{"", null, 1}; var output = string.join(",", inputs); console.writeline(output == "");//prints false

> output = ",,1"

is wrong in native implementation?

from msdn:

if first element of values null, join(string, object[]) method not concatenate elements in values instead returns string.empty.

which special case overload using object[]. note isn't true other overloads, string[] one.


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