这是我创建的一个示例方法来验证电子邮件地址，如果传递的字符串参数是一个有效的电子邮件地址，它返回true，否则返回false。

private boolean validateEmailAddress(String emailAddress){
    String  expression="^[\\w\\-]([\\.\\w])+[\\w]+@([\\w\\-]+\\.)+[A-Z]{2,4}$";  
       CharSequence inputStr = emailAddress;  
       Pattern pattern = Pattern.compile(expression,Pattern.CASE_INSENSITIVE);  
       Matcher matcher = pattern.matcher(inputStr);  
       return matcher.matches();
}

试试这个

public static final Pattern EMAIL_ADDRESS_PATTERN = Pattern.compile(

              "[a-zA-Z0-9\\+\\.\\_\\%\\-\\+]{1,256}" +
              "\\@" +
              "[a-zA-Z0-9][a-zA-Z0-9\\-]{0,64}" +
              "(" +
              "\\." +
              "[a-zA-Z0-9][a-zA-Z0-9\\-]{0,25}" +
              ")+"
          );

并在编辑文本

final String emailText = email.getText().toString();
EMAIL_ADDRESS_PATTERN.matcher(emailText).matches()

Java:

public static boolean isValidEmail(CharSequence target) {
    return (!TextUtils.isEmpty(target) && Patterns.EMAIL_ADDRESS.matcher(target).matches());
}

科特林：

fun CharSequence?.isValidEmail() = !isNullOrEmpty() && Patterns.EMAIL_ADDRESS.matcher(this).matches()

编辑:它将在Android 2.2+以上工作!!

编辑:添加缺失;

试试这个:

if (!emailRegistration.matches("[a-zA-Z0-9._-]+@[a-z]+\.[a-z]+")) {
 editTextEmail.setError("Invalid Email Address");
}

这是我创建的一个示例方法来验证电子邮件地址，如果传递的字符串参数是一个有效的电子邮件地址，它返回true，否则返回false。

private boolean validateEmailAddress(String emailAddress){
    String  expression="^[\\w\\-]([\\.\\w])+[\\w]+@([\\w\\-]+\\.)+[A-Z]{2,4}$";  
       CharSequence inputStr = emailAddress;  
       Pattern pattern = Pattern.compile(expression,Pattern.CASE_INSENSITIVE);  
       Matcher matcher = pattern.matcher(inputStr);  
       return matcher.matches();
}

public static boolean isEmailValid(String email) {
    boolean isValid = false;

    String expression = "^[\\w\\.-]+@([\\w\\-]+\\.)+[A-Z]{2,4}$";
    CharSequence inputStr = email;

    Pattern pattern = Pattern.compile(expression, Pattern.CASE_INSENSITIVE);
    Matcher matcher = pattern.matcher(inputStr);
    if (matcher.matches()) {
        isValid = true;
    }
    return isValid;
}