cannot implicitly convert type void to string

Question

cannot implicitly convert type void to string.. Below one. So, please anyone can help me how to convertor resolve this issue from void to string here.

 

public static string result1; 

 public static string getcomparedata1(string a,string b)

{

 form1 TC=new Form1();

result1 =TC.AutomateSourceToTargetStripMenuItem_Click();

return result1; 

}