使用未赋值的局部变量(带有字符串数组的非常简单的函数)。c#语言

I looked previous questions but it didn't help. I have a very simple function written in c#. It give me compiler error "Use of unassigned local variable 'linea' " (line (2)). What could be wrong? And could tell me how to correct it please?I looked previous questions but it didn't help.