Joke Collection Website - Public benefit messages - How does iphone choose a number to send text messages?

How does iphone choose a number to send text messages?

1.

Open the information of iPhone XR, and click the letter icon to create new information;

2.

Enter the mobile phone number of the recipient, or click the "+"sign behind the recipient to select the recipient from the address book;

3.

If the recipient number is not in the address book, clicking Edit SMS will pop up the current default SIM card; If the recipient ...

4.

Click the current default SIM card, and the secondary number and primary number will pop up at the bottom of the screen for selection.