Answers for "regular expression check string alphanumeric only"

regex except alphanumeric validation

string.replace(/[^a-zA-Z0-9_]+/g, '')

alphanumeric regex validation

validPattern = "^[a-zA-Z0-9]{10}$"; // alphanumeric exact 10 letters
this.projectForm = this.fb.group({
 ...
 CIG: [null, [Validators.required, Validators.pattern(this.validPattern)],