How to validate password strength with Angular 5 Validator Pattern

I took a stab at this with Angular’s built-in pattern validator and was able to come up with the following that checks for:

• At least 8 characters in length
• Lowercase letters
• Uppercase letters
• Numbers

• Special characters

  password: [
    '',
    [
      Validators.required,
      Validators.pattern('(?=.*[a-z])(?=.*[A-Z])(?=.*[0-9])(?=.*[$@$!%*?&])[A-Za-z\d$@$!%*?&].{8,}')
     ]
  ]
  

I’ll add that I’m by no means a regex expert. This is simply what worked for me for a closely related case to the OP. Maybe it will help someone else. Mozilla’s documentation helped a lot in figuring this out, specifically the Writing a regular expression pattern section.