Add new item on Standart Context Menu X++

Hi everyone and good working,

I m trying to add new item standart context menu ,it is like:

filter by field

filter by selection

Sort Ascending

MY FİELD (when clikck it I do something like open a form!!),

How can I do this,I search some code but all of them make new popup menu ,

Thanks for your answer

Menus → SysContextMenu - add here…

thanks your answer

I now it ,but ıf I add there all context open with my field,I want to only one form use it,Example,I have a form called myform

I want to use there my special context menu,If I add Syscontext menu it is seem all menu.