iframe parent-child page value transfer problem_html/css_WEB-ITnose

Parent page A.jsp
b.jsp is the child page
After the b.jsp page is executed, I get a string I need Pass this string to the A.jsp page and display it in the text tag of the parent page. The parent page cannot be refreshed
What needs to be done
Thank you!

Reply to discussion (solution)

Use js to assign value, roughly
parent.document.name.value='ok'
The specific situation needs to be analyzed in detail

Use js to assign the value, roughly
parent.document.name.value='ok'
The specific situation needs to be analyzed in detail

I know it
$(window.parent.$("#content").html(obj.fileName)); //The child page passes the value to the parent page
$(window.parent.content_assignment(obj .fileName)); //The child page calls the parent page method
Thank you