UITextField how to disable the paste?(UITextField 禁止粘贴)

overrides the canPerformAction:withSender: method to return NO for actions that you don't want to allow:

- (BOOL)canPerformAction:(SEL)action withSender:(id)sender
    {
        if (action == @selector(paste:))
            return NO;
        if (action == @selector(select:))   
            return NO;   
        if (action == @selector(selectAll:))   
            return NO;  
        return [super canPerformAction:action withSender:sender];
    }

In Above Code you need to write only for paste

Another way

-(BOOL)canPerformAction:(SEL)action withSender:(id)sender {
    UIMenuController *menuController = [UIMenuController sharedMenuController];
    if (menuController) {
        [UIMenuController sharedMenuController].menuVisible = NO;
    }
    return NO;
}

Also check This link