how to add a new Many-To-Many table data using entity framework -

iam working on asp.net mvc web application , entity framework. have following table:-

• user table (userid,name,age, etc)

• group table, (groupid,name,description,etc)

• and usergroup table. (userid , groupid)

but since usergroup table pure many-to-many relationship stores both userid & groupid , not mapped using entity framework. know groupid , userid , how can populate relation between them. should such :-

 group.where(a=.a.groupid).singleordefualt().user.add(//something here !!!) 

var group = db.groups.find(groupid); if (group != null) {     group.users.add(user); // add user existing users     db.savechanges(); } 

or

user.groups.add(group); // add group existing groups db.savechanges(); 

if want replace users, assign new collection:

group.users = new list<user> { user }; db.savechanges(); 

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if want remove user it's groups , add user other group:

var user = db.users.find(userid); user.groups.clear(); var group = db.groups.find(groupid); user.groups.add(group); db.savechanges(); 

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if want remove users group:

var group = db.groups.find(groupid); // group var usertoremove = group.users.last(); // select user, e.g. last 1 group.users.remove(usertoremove); // remove user group users db.savechanges(); // save changes