why there is one file of mainform_hide.cs ?

If that form is not being used at any place in your project then you are good to remove it.

Also make sure that class name is same for both forms or not and Class name is used as partial class or not. Because in .Net you have provision of partial class concept where you can write partial code in one file and other code (of same class) is other files.

This is same like, system is creating a designer file for windows form.

System is not creating any file by it self so you have to make sure from above two scenarios and if those are not the case then you are good to remove.

Thanks
Rushikesh Joshi

Hi,

First, is this typo mistake or you have the same file name ? (MianForm_hide.cs) instead (MainForm_hide.cs) ?

there is no such auto generated file required. check what code you have written in it.

if there is some function inside this form then find all references to see if it is being used anywhere. also check the filename in your project if you are creating instance somewhere. once you confirm that it is not required. you can exclude that file for some time and once you are sure then you can delete it.

Thanks
-Amit

it may due to my mistake to add this file in my progrm, so delete it to solve this problem