Android Studio 通過(guò)登錄功能介紹SQLite數(shù)據(jù)庫(kù)的使用流程

create table if not exists 表名(字段1 類(lèi)型(長(zhǎng)度),字段2 類(lèi)型(長(zhǎng)度),...)

drop table if exists 表名

insert into 表名 (字段1,字段2,字段3 ...) values (值1,值2,值3 ...);

insert into 目標(biāo)數(shù)據(jù)表 select * from 源數(shù)據(jù)表;

delete from 表名 where 條件表達(dá)式

update 表名 set 字段1=值1,字段2=值2... where 條件表達(dá)式

select * from 表名 where 條件表達(dá)式

package com.hyl.dao;
import android.content.Context;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import android.database.sqlite.SQLiteDatabase.CursorFactory;
/**
 * @programName: DBOpenHelper.java
 * @programFunction: database helper class
 * @createDate: 2018/09/29
 * @author: AnneHan
 * @version:
 * xx.  yyyy/mm/dd  ver  author  comments
 * 01.  2018/09/29  1.00  AnneHan  New Create
 */
public class DBOpenHelper extends SQLiteOpenHelper {
  public DBOpenHelper(Context context,String name, CursorFactory factory,
            int version){
    super(context, name, factory, version);
  }
  @Override
  //首次創(chuàng)建數(shù)據(jù)庫(kù)的時(shí)候調(diào)用，一般可以執(zhí)行建庫(kù)，建表的操作
  //Sqlite沒(méi)有單獨(dú)的布爾存儲(chǔ)類(lèi)型，它使用INTEGER作為存儲(chǔ)類(lèi)型，0為false，1為true
  public void onCreate(SQLiteDatabase db){
    //user table
    db.execSQL("create table if not exists user_tb(_id integer primary key autoincrement," +
        "userID text not null," +
        "pwd text not null)");
  }
  @Override//當(dāng)數(shù)據(jù)庫(kù)的版本發(fā)生變化時(shí)，會(huì)自動(dòng)執(zhí)行
  public void onUpgrade(SQLiteDatabase db,int oldVersion,int newVersion){
  }
}

/**
 * login event
 * @param v
 */
public void OnMyLoginClick(View v){
  //判斷賬號(hào)/密碼是否有輸入的處理...
  //調(diào)用DBOpenHelper （qianbao.db是創(chuàng)建的數(shù)據(jù)庫(kù)的名稱）
  DBOpenHelper helper = new DBOpenHelper(this,"qianbao.db",null,1);
  SQLiteDatabase db = helper.getWritableDatabase();
  //根據(jù)畫(huà)面上輸入的賬號(hào)/密碼去數(shù)據(jù)庫(kù)中進(jìn)行查詢（user_tb是表名）
  Cursor c = db.query("user_tb",null,"userID=? and pwd=?",new String[]{參數(shù)1的值,參數(shù)2的值},null,null,null);
  //如果有查詢到數(shù)據(jù)
  if(c!=null && c.getCount() >= 1){
    //可以把查詢出來(lái)的值打印出來(lái)在后臺(tái)顯示/查看
    /*String[] cols = c.getColumnNames();
    while(c.moveToNext()){
      for(String ColumnName:cols){
        Log.i("info",ColumnName+":"+c.getString(c.getColumnIndex(ColumnName)));
      }
    }*/
    c.close();
    db.close();
    this.finish();
  }
  //如果沒(méi)有查詢到數(shù)據(jù)
  else{
    Toast.makeText(this, "手機(jī)號(hào)或密碼輸入錯(cuò)誤！", Toast.LENGTH_SHORT).show();
  }
}

import com.hyl.dao.DBOpenHelper;
import android.content.ContentValues;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
/**
 * register event
 * @param v
 */
public void OnMyRegistClick(View v){
  //對(duì)用戶輸入的值的格式進(jìn)行判斷的處理...
  //調(diào)用DBOpenHelper
  DBOpenHelper helper = new DBOpenHelper(this,"qianbao.db",null,1);
  SQLiteDatabase db = helper.getWritableDatabase();
  //根據(jù)畫(huà)面上輸入的賬號(hào)去數(shù)據(jù)庫(kù)中進(jìn)行查詢
  Cursor c = db.query("user_tb",null,"userID=?",new String[]{參數(shù)1的值},null,null,null);
  //如果有查詢到數(shù)據(jù)，則說(shuō)明賬號(hào)已存在
  if(c!=null && c.getCount() >= 1){
    Toast.makeText(this, "該用戶已存在", Toast.LENGTH_SHORT).show();
    c.close();
  }
  //如果沒(méi)有查詢到數(shù)據(jù)，則往數(shù)據(jù)庫(kù)中insert一筆數(shù)據(jù)
  else{
    //insert data
    ContentValues values= new ContentValues();
    values.put("userID","畫(huà)面上輸入的值");
    values.put("pwd","畫(huà)面上輸入的值");
    long rowid = db.insert("user_tb",null,values);
    Toast.makeText(this, "注冊(cè)成功", Toast.LENGTH_SHORT).show();//提示信息
    this.finish();
  }
  db.close();
}

  /**
 * confirm event
 */
private void confirmInfo() {
  //對(duì)界面上用戶輸入的值進(jìn)行判斷的處理...

  //調(diào)用DBOpenHelper
  DBOpenHelper helper = new DBOpenHelper(this,"qianbao.db",null,1);
  SQLiteDatabase db = helper.getWritableDatabase();
  //根據(jù)畫(huà)面上輸入的賬號(hào)/密碼去數(shù)據(jù)庫(kù)中進(jìn)行查詢
  Cursor c = db.query("user_tb",null,"userID=?",new String[]{editPhone.getText().toString()},null,null,null);
  //如果有查詢到數(shù)據(jù)，說(shuō)明賬號(hào)存在，可以進(jìn)行密碼重置操作
  if(c!=null && c.getCount() >= 1){
    ContentValues cv = new ContentValues();
    cv.put("pwd", editPhone.getText().toString());//editPhone界面上的控件
    String[] args = {String.valueOf(editPhone.getText().toString())};
    long rowid = db.update("user_tb", cv, "userID=?",args);
    c.close();
    db.close();
    Toast.makeText(this, "密碼重置成功！", Toast.LENGTH_SHORT).show();
    this.finish();
  }
  //如果沒(méi)有查詢到數(shù)據(jù)，提示用戶到注冊(cè)界面進(jìn)行注冊(cè)
  else{
    new AlertDialog.Builder(this)
        .setTitle("提示")
        .setMessage("該用戶不存在，請(qǐng)到注冊(cè)界面進(jìn)行注冊(cè)！")
        .setPositiveButton("確定", new DialogInterface.OnClickListener() {
          public void onClick(DialogInterface dialog, int whichButton) {
            setResult(RESULT_OK);
            Intent intent=new Intent(當(dāng)前重置密碼界面.this,注冊(cè)界面.class);
            當(dāng)前重置密碼界面.this.startActivity(intent);
          }
        })
        .setNegativeButton("取消", new DialogInterface.OnClickListener() {
          public void onClick(DialogInterface dialog, int whichButton) {
            return;
          }
        })
        .show();
  }
}