我們android 開發人員都會與到 登入註冊，郵箱驗證等問題 ，我們需要if判斷 ，簡單邏輯 比較好些，隨著產品的需求，格式越來越多，邏輯越來越複雜，下面 給大家推薦 一下自己封裝的一個工具類 裡面對應的正的表示式等多個簡單實用

首先是一個工具類  

public class Util {

/*    public static BookCommentAdapter upd;

    public static BookDetailAdapter bda;*/
    public static Map<String, Long> map;

    public static String ChangeCode(String str) {
        String utf8string = null;
        try {
            utf8string = URLEncoder.encode(URLEncoder.encode(str, "UTF-8"),
                    "UTF-8");
           // utf8string = URLEncoder.encode(str, "UTF-8");

            return utf8string;
        } catch (UnsupportedEncodingException e2) {
            e2.printStackTrace();
        }
        return utf8string;
    }

    public static boolean mobileMumVerify(String phoneNum) {
        //String regExp = "^((13[0-9])|(15[^4])|(18[0,2,3,5-9])|(17[0-8])|(147)|199|198|166)\\d{8}$";
        String regExp = "^((13[0-9])|(15[^4])|(18[0-9])|(17[0-8])|(147)|199|198|166)\\d{8}$";
        Pattern p = Pattern.compile(regExp);
        Matcher m = p.matcher(phoneNum);
        return m.matches();
    }

    public static boolean isMobileNO(String mobiles) {
        String telRegex = "13\\d{9}|14[57]\\d{8}|15[012356789]\\d{8}|18[012356789]\\d{8}|17[01678]\\d{8}";
        if (TextUtils.isEmpty(mobiles)) return false;
        else return mobiles.matches(telRegex);
    }

    public static boolean passWordVerify(String pass) {
        Pattern p = Pattern.compile("^[A-Za-z0-9]{6,12}$");
        //Pattern p = Pattern.compile("^(?![0-9]+$)(?![a-zA-Z]+$)[0-9A-Za-z_]{6,12}$");
        return p.matcher(pass).matches();
    }

    public static boolean mailAddressVerify(String mailAddress) {
        String emailExp = "^([a-zA-Z0-9_\\-\\.]+)@((\\[[0-9]{1,3}\\.[0-9]{1,3}\\.[0-9]{1,3}\\.)|(([a-zA-Z0-9\\-]+\\.)+))([a-zA-Z]{2,4}|[0-9]{1,3})(\\]?)$";
        Pattern p = Pattern.compile(emailExp);
        return p.matcher(mailAddress).matches();
    }

    public static int dpToPx(Context context, int dp) {
        return (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, dp,
                context.getResources().getDisplayMetrics());
    }

    public static int px2sp(Context context, float pxValue) {
        final float fontScale = context.getResources().getDisplayMetrics().scaledDensity;
        return (int) (pxValue / fontScale + 0.5f);
    }

    public static String timeFormat(long time) {
        return new SimpleDateFormat("yyyy-MM-dd", Locale.CHINA).format(time);
    }

    public static String timeFormatForS(long time) {
        return new SimpleDateFormat("yyyy-MM-dd HH:mm:ss", Locale.CHINA)
                .format(time);
    }

    public static String getExt(String url) {
        if (TextUtils.isEmpty(url))
            return null;
        return url.substring(url.lastIndexOf("."), url.length());
    }

    private static long exitTime = 0;

/*    public static void ExitApp(Context c) {
        if (System.currentTimeMillis() - exitTime > 2000) {
            showToast(c, "再按一次返回鍵退出");
            exitTime = System.currentTimeMillis();
        } else {
            SystemExit.exitSystem();
        }
    }*/

    public static boolean isNetworkAvailable(Context context) {
        ConnectivityManager connectivity = (ConnectivityManager) context
                .getSystemService(Context.CONNECTIVITY_SERVICE);
        if (connectivity == null) {
            return false;
        } else {
            NetworkInfo[] info = connectivity.getAllNetworkInfo();
            if (info != null) {
                for (int i = 0; i < info.length; i++) {
                    if (info[i].getState() == NetworkInfo.State.CONNECTED
                            || info[i].getState() == NetworkInfo.State.CONNECTING) {
                        return true;
                    }
                }
            }
        }
        return false;
    }





    public static Uri getOutputMediaFileUri(Context c) {
        return Uri.fromFile(getOutputMediaFile(c));
    }




    public static File getOutputMediaFile(Context c) {
        // Create a media file name
        // String timeStamp = new SimpleDateFormat("yyyyMMdd_HHmmss",
        // Locale.CHINA)
        // .format(new Date());
        File mediaFile;
        mediaFile = new File(
                c.getExternalFilesDir(Environment.DIRECTORY_PICTURES)
                        + File.separator + "IMG_" + "temp" + ".png");

        return mediaFile;
    }


}
 

public class TextsActivity extends AppCompatActivity {
Button btn;
EditText phone,psw,email;


    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_texts);
        btn= findViewById(R.id.btn);
        phone=findViewById(R.id.phone);
        psw=findViewById(R.id.psw);
        email=findViewById(R.id.email);

        btn.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {

                String name = phone.getText().toString().trim();
                String pass = psw.getText().toString().trim();
                String yx = email.getText().toString().trim();


                if(TextUtils.isEmpty(name))
                {
                    Toast.makeText(TextsActivity.this,"手機號不能為空",Toast.LENGTH_LONG).show();
                    return;
                }
                if(TextUtils.isEmpty(pass))
                {
                    Toast.makeText(TextsActivity.this,"密碼為空",Toast.LENGTH_LONG).show();
                    return;
                }
                if(!Util.mobileMumVerify(name))
                {
                    Toast.makeText(TextsActivity.this,"手機格式不正確",Toast.LENGTH_LONG).show();
                    return;
                }

                if (!Util.passWordVerify(pass)) {

                    Toast.makeText(TextsActivity.this,"密碼格式不符,6-12位數字或者字母",Toast.LENGTH_LONG).show();
                    return;
                }
                if (!Util.mailAddressVerify(yx)) {
                    Toast.makeText(TextsActivity.this,"郵箱格式不正確",Toast.LENGTH_LONG).show();
                    return;
                }


            }
        });


    }

}