问题
I am using MFMailComposeViewController for sending emails. Mine is universal app and toField of email is having 2 mail ids.
(1) Each email id is around 30 characters long. In iPhone I see it as "+2 recipients". (In iPad able to visualize the email ids in toField.) And when I Googled, found that there is a restriction of 40 characters of text limit in toField. How to avoid this problem.
(2) Also if I click on "+2 recipients" it is displaying the email ids but then not able to hide the keypad which is opened.
回答1:
You have no control over those types of settings. The MFMailComposeViewController is a fire and forget style email solution for your application that provides an interface your users are familiar with.
The 40 character limit refers to the limit before they are shortened, your emails aren't being cut off. You won't be able to lift that limit. It is what it is. If you want to create a custom email form you'll have to build your own IMAP framework to go with it sadly.
Security is a high priority on iOS and as such, things like the user's email addresses and content is closely guarded.
来源：https://stackoverflow.com/questions/15494377/mfmailcomposeviewcontroller-email-to-field-limit-40-in-iphone