如何检查edittext的文本是否为电子邮件地址？

edittext不使用javascript正则表达式如何检查电子邮件地址是否是文本？在这里，我使用了inputtype="textEmailAddress"这种方法，但是没有错误消息显示。

/**
 * method is used for checking valid email id format.
 * 
 * @param email
 * @return boolean true for valid false for invalid
 */
public static boolean isEmailValid(String email) {
    String expression = "^[\\w\\.-]+@([\\w\\-]+\\.)+[A-Z]{2,4}$";
    Pattern pattern = Pattern.compile(expression, Pattern.CASE_INSENSITIVE);
    Matcher matcher = pattern.matcher(email);
    return matcher.matches();
}

在此函数中传递您的编辑文本字符串。

要进行正确的电子邮件验证，您需要服务器端身份验证

请注意，Android现在有一个内置方法，请参见下面的答案。

在Android 2.2+上，使用以下命令：

boolean isEmailValid(CharSequence email) {
   return android.util.Patterns.EMAIL_ADDRESS.matcher(email).matches();
}

例如：

EditText emailid = (EditText) loginView.findViewById(R.id.login_email);
String getEmailId = emailid.getText().toString();

// Check if email id is valid or not
       if (!isEmailValid(getEmailId)){
        new CustomToast().Show_Toast(getActivity(), loginView,
                "Your Email Id is Invalid.");
 }

请按照以下步骤

第1步 ：

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity" >

    <EditText
        android:id="@+id/editText_email"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginLeft="20dp"
        android:layout_marginRight="20dp"
        android:layout_below="@+id/textView_email"
        android:layout_marginTop="40dp"
        android:hint="Email Adderess"
        android:inputType="textEmailAddress" />

    <TextView
        android:id="@+id/textView_email"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentTop="true"
        android:layout_centerHorizontal="true"
        android:layout_marginTop="30dp"
        android:text="Email Validation Example" />

</RelativeLayout>

第2步：

import android.app.Activity;
import android.os.Bundle;
import android.text.Editable;
import android.text.TextWatcher;
import android.widget.EditText;

第三步：

public class MainActivity extends Activity {

private EditText email;

private String valid_email;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    initilizeUI();
}

/**
 * This method is used to initialize UI Components
 */
private void initilizeUI() {
    // TODO Auto-generated method stub

    email = (EditText) findViewById(R.id.editText_email);

    email.addTextChangedListener(new TextWatcher() {

        @Override
        public void onTextChanged(CharSequence s, int start, int before,
                int count) {
            // TODO Auto-generated method stub

        }

        @Override
        public void beforeTextChanged(CharSequence s, int start, int count,
                int after) {
            // TODO Auto-generated method stub

        }

        @Override
        public void afterTextChanged(Editable s) {
            // TODO Auto-generated method stub

            // TODO Auto-generated method stub
            Is_Valid_Email(email); // pass your EditText Obj here.
        }

        public void Is_Valid_Email(EditText edt) {
            if (edt.getText().toString() == null) {
                edt.setError("Invalid Email Address");
                valid_email = null;
            } else if (isEmailValid(edt.getText().toString()) == false) {
                edt.setError("Invalid Email Address");
                valid_email = null;
            } else {
                valid_email = edt.getText().toString();
            }
        }

        boolean isEmailValid(CharSequence email) {
            return android.util.Patterns.EMAIL_ADDRESS.matcher(email)
                    .matches();
        } // end of TextWatcher (email)
    });

}

}

我编写了一个扩展EditText的库，该库本身支持某些验证方法，并且实际上非常灵活。

如我所写，当前 本地支持的（通过xml属性）验证方法是：

1. regexp：用于自定义regexp
2. numeric：仅用于数字字段
3. alpha：仅用于alpha字段
4. alphaNumeric：你猜怎么着？
5. email：检查该字段是否为有效的电子邮件
6. creditCard：使用Luhn算法检查字段是否包含有效的信用卡
7. phone：检查字段中是否包含有效的电话号码
8. domainName：检查字段是否包含有效的域名（始终通过API级别<8的测试）
9. ipAddress：检查该字段包含有效的ip地址webUrl：检查该字段包含有效的url（始终通过API Level <8中的测试）
10. nocheck：它不检查任何内容。（默认）

您可以在这里查看：https : //github.com/vekexasia/android-form-edittext

希望你喜欢它 ：）

在我链接的页面中，您还可以找到电子邮件验证的示例。我将在此处复制相对代码段：

<com.andreabaccega.widget.FormEditText
       style="@android:style/Widget.EditText"
       whatever:test="email"
       android:id="@+id/et_email"
       android:layout_width="match_parent"
       android:layout_height="wrap_content"
       android:hint="@string/hint_email"
       android:inputType="textEmailAddress"
       />  

还有一个测试应用程序展示了库的可能性。

这是验证电子邮件字段的应用程序的屏幕截图。

如答案之一所述，您可以使用以下Patterns类：

public final static boolean isValidEmail(CharSequence target) {
    if (target == null) 
        return false;

    return android.util.Patterns.EMAIL_ADDRESS.matcher(target).matches();
}

如果您偶然支持的API级别小于8，那么您只需将Patterns.java文件复制到项目中并进行引用即可。您可以Patterns.java从此链接获取源代码

您可以使用android.util.Patterns package。

EditText email = (EditText)findViewById(R.id.user_email);

if(Patterns.EMAIL_ADDRESS.matcher(email.getText().toString()).matches())
    Toast.makeText(this, "Email is VALID.", Toast.LENGTH_SHORT).show();
else
    Toast.makeText(this, "Email is INVALID.", Toast.LENGTH_SHORT).show();

以下代码对您应该有用。

String email;
check.setOnClickListener(new OnClickListener() {


                public void onClick(View arg0) {

                    checkEmail(email);
                    if (checkMail) {
                        System.out.println("Valid mail Id");
                    }
                }
            });

        }
    }

    public static boolean checkEmail(String email) {

        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}" + ")+");
        return EMAIL_ADDRESS_PATTERN.matcher(email).matches();
    }

电子邮件是您的电子邮件ID。

  public boolean validateEmail(String email) {

    Pattern pattern;
    Matcher matcher;
    String EMAIL_PATTERN = "^[_A-Za-z0-9-]+(\\.[_A-Za-z0-9-]+)*@[A-Za-z0-9]+(\\.[A-Za-z0-9]+)*(\\.[A-Za-z]{2,})$";
    pattern = Pattern.compile(EMAIL_PATTERN);
    matcher = pattern.matcher(email);
    return matcher.matches();

    }

可以按照其他答案中所述使用Apache Commons Validator。

步骤：1）从此处下载jar文件

步骤：2）将其添加到您的项目库中

导入：

import org.apache.commons.validator.routines.EmailValidator;

代码：

String email = "myName@example.com";
boolean valid = EmailValidator.getInstance().isValid(email);

并允许本地地址：

boolean allowLocal = true;
boolean valid = EmailValidator.getInstance(allowLocal).isValid(email);

对于电子邮件地址验证，请尝试以下简单代码。

    String email = inputEmail.getText().toString().trim();

    if (!Patterns.EMAIL_ADDRESS.matcher(email).matches())
    {
        inputEmail.setError("Enter Valid Email Address");
        inputEmail.requestFocus();
    }

一种简单的方法

    private boolean isValidEmail(String email)
{
    String emailRegex ="^[_A-Za-z0-9-\\+]+(\\.[_A-Za-z0-9-]+)*@[A-Za-z0-9-]+(\\.[A-Za-z0-9]+)*(\\.[A-Za-z]{2,})$";
    if(email.matches(emailRegex))
    {
        return true;
    }
    return false;
}

   I Hope this code is beneficial for you

    public class Register extends Activity 
      {
       EditText FirstName, PhoneNo, EmailId,weight;
       Button Register;
       private static final Pattern EMAIL_PATTERN = Pattern
        .compile("^[_A-Za-z0-9-]+(\\.[_A-Za-z0-9-]+)*@[A-Za-z0-9]+(\\.[A-Za-z0-9]+)*(\\.[A-Za-z]{2,})$");


   private static final Pattern USERFIRSTNAME_PATTERN = Pattern
        .compile("[a-zA-Z0-9]{1,250}");
   private static final Pattern PHONE_PATTERN = Pattern
        .compile("[a-zA-Z0-9]{1,250}");
       @Override
   public void onCreate(Bundle savedInstanceState) {
    // TODO Auto-generated method stub
        super.onCreate(savedInstanceState);
        setContentView(R.layout.register);


        Register=(Button) findViewById(R.id.register);

        FirstName=(EditText)findViewById(R.id.person_firstname);

            PhoneNo =(EditText)findViewById(R.id.phone_no);
            EmailId=(EditText)findViewById(R.id.email_id);
            weight=(EditText) findViewById(R.id.weight);

         Register.setOnClickListener(new View.OnClickListener() {

            @Override
            public void onClick(View v) {

                sFirstName= FirstName.getText().toString();
                 sPhoneNo= PhoneNo.getText().toString();
                sEmailId= EmailId.getText().toString();
                sweight= weight.getText().toString(); 

                if(sFirstName.equals("")||sPhoneNo.equals("")||sEmailId.equals("")||sweight.equals(""))
                {
                    if ((!CheckUsername(sFirstName))) 
                     {
                     Toast.makeText(Register.this, "FirstName can not be null",Toast.LENGTH_LONG).show();
                     }
                   else if ((!Checkphoneno(sPhoneNo)))
                       {
                    Toast.makeText(Register.this, "ENTER VALID mobile no ",Toast.LENGTH_LONG).show();
                       }
                    else if ((!CheckEmail(sEmailId)))
                       {
                      Toast.makeText(Register.this, "ENTER VALID EMAIL ID",Toast.LENGTH_LONG).show();
                       }
                    else if ((!Checkweight(sweight)))
                      {
                    Toast.makeText(Register.this, "ENTER Weight in kg",Toast.LENGTH_LONG).show();
                      }
               }

            }
                private boolean CheckEmail(String sEmailId) {

                    return EMAIL_PATTERN.matcher(sEmailId).matches();
                }



                private boolean CheckUsername(String sFirstName) {

                    return USERFIRSTNAME_PATTERN.matcher(sFirstName).matches();
                }
                private boolean Checkphoneno(String sPhoneNo) {

                    return PHONE_PATTERN.matcher(sPhoneNo).matches();
                }
                private boolean Checkweight(String sweight) {

                    return Weight_PATTERN.matcher(sweight).matches();
                }


        });

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

    String expression = "^(([\\w-]+\\.)+[\\w-]+|([a-zA-Z]{1}|[\\w-]{2,}))@"
            + "((([0-1]?[0-9]{1,2}|25[0-5]|2[0-4][0-9])\\.([0-1]?"
            + "[0-9]{1,2}|25[0-5]|2[0-4][0-9])\\."
            + "([0-1]?[0-9]{1,2}|25[0-5]|2[0-4][0-9])\\.([0-1]?"
            + "[0-9]{1,2}|25[0-5]|2[0-4][0-9])){1}|"
            + "([a-zA-Z]+[\\w-]+\\.)+[a-zA-Z]{2,4})$";
    // "^[\\w\\.-]+@([\\w\\-]+\\.)+[A-Z]{2,4}$";
    CharSequence inputStr = email;

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

对于电子邮件验证，请尝试此操作。

public boolean checkemail(String email)
{

    Pattern pattern = Pattern.compile(".+@.+\\.[a-z]+");
    Matcher matcher = pattern.matcher(email);
    return matcher.matches();

}

您可以通过正则表达式进行检查

    public boolean isValid(String strEmail)
    {
        pattern = Pattern.compile("^[_A-Za-z0-9-\\+]+(\\.[_A-Za-z0-9-]+)*@[A-Za-z0-9-]+(\\.[A-Za-z0-9]+)*(\\.[A-Za-z]{2,})$");
            matcher = pattern.matcher(strEmail);

        if (strEmail.isEmpty()) {
           return false;
        } else if (!matcher.matches()) {
            return false;
        }
        else
        {
        return true;
        }
     }

private boolean isValidEmailID(String email) {
    String PATTERN = "^[_A-Za-z0-9-\\+]+(\\.[_A-Za-z0-9-]+)*@"+ "[A-Za-z0-9-]+(\\.[A-Za-z0-9]+)*(\\.[A-Za-z]{2,})$";
    Pattern pattern = Pattern.compile(PATTERN);
    Matcher matcher = pattern.matcher(email);
    return matcher.matches();
}

有关更多验证，请单击此处

使用android.util.Patterns和Kotlin，这非常简单。一线函数返回布尔值。

fun validateEmail(email: String) = Patterns.EMAIL_ADDRESS.matcher(email)