4

我需要获取用户名和密码...我正在我的应用程序中进行密码恢复，所以这是我的 DB 代码：

public String getEmailAddr() throws SQLException {
    Cursor mCursor = db.rawQuery(
        "SELECT Username, Passwords FROM " + 
        USERS_TABLE + " WHERE EmailNO=?",null);

    if (mCursor != null) {           

        if(mCursor.getCount() > 0 {
            //return obj1.getpassword();
        }
    }

    //return false;
    return obj1.getpassword();
}

当用户输入电子邮件地址时，它必须首先检查是否存在并使用我的活动代码发送电子邮件返回密码和用户名：

public void onClick(View v) {
    String EmailAddress = txtEmailAddress.getText().toString();
    try {
        if(EmailAddress.length() > 0) {
            DBAdapter  dbUser = new DBAdapter (RecoverPassword.this);
            dbUser.open();

            if(dbUser.getEmailAddress(EmailAddress)) {
                Toast.makeText(RecoverPassword.this,
                    "Email Successfully ", 
                    Toast.LENGTH_LONG).show();
                    Toast.makeText String to = 
                        txtEmailAddress.getText().toString();
                    //String subject = EmailAddress.getText().toString();
                    // String message = EmailAddress.getText().toString();
                    Intent email = new Intent(Intent.ACTION_SEND);
                    email.putExtra(Intent.EXTRA_EMAIL, new String[]{ to});
                    email.putExtra(Intent.EXTRA_SUBJECT, "Password Recovery");
                    email.putExtra(Intent.EXTRA_TEXT, dbUser.getEmailAddr());
                    //need this to prompts email client only 
                    email.setType("message/rfc822");
                    startActivity(Intent.createChooser(email, "gmail :"));                 
                }

                else {
                    Toast.makeText(RecoverPassword.this,
                        "Invalid Email", Toast.LENGTH_LONG).show();
                    txtEmailAddress.setText("");
                }

                dbUser.close();
            }
        }

        catch(Exception e) {
            Toast.makeText(RecoverPassword.
            this,e.getMessage(), Toast.LENGTH_LONG).show();
        }

        Please help me to check what is wrong...but there is no error but it cant return 
        username and password to the email sent
4

2 回答 2

3

我对您的代码感到困惑，但是当您想从中获取数据Cursor时

String[] whereArgs = new String[<data>];
    Cursor mCursor = db.rawQuery("SELECT Username, Passwords FROM " + USERS_TABLE + " WHERE EmailNO = ?", whereArgs);
    mCursor.moToFirst();

    if(mCursor.getCount() > 0} {
       String userName = mCursor.getString(0);
       String password = mCursor.getString(1);

    }

您必须使用从数据库返回数据的getters提供实例。Cursor

编辑：

我没有注意到你使用 whereArgs 所以当你使用WHERE子句时，你必须指定 whereArgs 因为String[]它包含将被替换的数据而不是? 字符。

您可以使用关闭数据库：

@Override
protected void onDestroy() {
    super.onDestroy();
    if (yourDatabase != null) {
        yourDatabase.close();
    }
}

或者在打开你的数据库的每项工作之后，你应该close()db.

于 2012-05-30T09:33:25.707 回答
1

在

Cursor mCursor = db.rawQuery("SELECT Username, Passwords FROM " + USERS_TABLE + " WHERE
EmailNO=?",null);

您没有提供 EmailNO 的值。将值替换为null。

编辑：我认为你的代码应该是这样的：

public boolean getEmailAddress(String emailNo) 
    throws SQLException { //pass the EmailNo which you want in where clause
    Cursor mCursor = db.rawQuery(
        "SELECT Username, Passwords FROM sddashsd WHERE 
        EmailNO='"+emailNo+"'",null);

        if (mCursor != null) {         
            if(mCursor.getCount() > 0)
                return true;
        else 
            return false;
        }
    }

并在此处编辑您的代码：

public void onClick(View v) {
    String EmailAddress = 
        txtEmailAddress.getText().toString();

    try {
        if(EmailAddress.length() > 0) {
            DBAdapter  dbUser = new DBAdapter (RecoverPassword.this);
            dbUser.open();

            if(dbUser.getEmailAddress(EmailAddress)) {
                Toast.makeText(RecoverPassword.this,
                    "Email Successfully ", Toast.LENGTH_LONG).show();
                String to = txtEmailAddress.getText().toString();
                //String subject = EmailAddress.getText().toString();
                // String message = EmailAddress.getText().toString();
                Intent email = new Intent(Intent.ACTION_SEND);
                email.putExtra(Intent.EXTRA_EMAIL, new String[]{ to});
                email.putExtra(Intent.EXTRA_SUBJECT, "Password Recovery");
                email.putExtra(Intent.EXTRA_TEXT, dbUser.getEmailAddr());
                //need this to prompts email client only
                email.setType("message/rfc822");
                startActivity(Intent.createChooser(email, "gmail"));
            }

            else {
                Toast.makeText(RecoverPassword.this,"Invalid Email", 
                    Toast.LENGTH_LONG).show();                             
                    txtEmailAddress.setText("");
            }

        }

    }

    catch(Exception e) {
        Toast.makeText(RecoverPassword.this,
            e.getMessage(), Toast.LENGTH_LONG).show();
    }

    finally {
        dbUser.close();  
    }
于 2012-05-30T09:34:35.500 回答