Android数据库相关代码解读(1)

Android数据库的操作方法多样化，掌握这些应用技巧对于我们的实际开发起着非常重要的作用。我们在这里就为大家介绍了一下相关操作技巧。

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在Android 手机操作系统进行实际开发中，进场会应用到数据库。而且在这一平台中对数据库的应用方法比较简单灵活。我们在这里就为大家详细介绍了相关方法，希望可以给大家带来一些帮助。

昨天进行了GUI界面设计，感受了一下android初次设计的愉悦，今天接着学习其SQLite数据库试用，将昨天的例子中数据存到数库中，并读取查看一下。 具体看代码（原写的有点问题，再改写如下）：

1) Android数据库之库操作类：

package com.topsun;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.util.Log;
public class DBHelper {
private static final String TAG = "UserDB_DBHelper.java";
private static final String DataBaseName = "UserDB";
SQLiteDatabase db;
Context context;
public DBHelper(Context context) {
this.open(context);
}
private void createTabel() {
// TODO Auto-generated method stub
String sql = "";
try {
sql = "CREATE TABLE IF NOT EXISTS TestUser (ID INTEGER PRIMARY KEY autoincrement, NAME TEXT, SEX TEXT, AGES INTEGER)";
this.db.execSQL(sql);
Log.v(TAG, "Create Table TestUser ok");
} catch (Exception e) {
Log.v(TAG, "Create Table TestUser fail");
} finally {
//this.db.close();
Log.v(TAG, "Create Table TestUser ");
}
}
public boolean save(String name, String sex, Integer ages) {
String sql = "insert into TestUser values(null,'" + name + "','" + sex
+ "'," + ages + ")";
try {
this.db.execSQL(sql);
Log.v(TAG, "insert Table TestUser 1 record ok");
return true;
} catch (Exception e) {
Log.v(TAG, "insert Table TestUser 1 record fail");
return false;
} finally {
//this.db.close();
Log.v(TAG, "insert Table TestUser ");
}
}
public Cursor loadAll() {
Cursor cur = db.query("TestUser", new String[] { "ID", "NAME","SEX","AGES"}, null,
null, null, null, null);
return cur;
}
public void open(Context context){
if (null == db || !this.db.isOpen()){
this.context = context;
this.db = context.openOrCreateDatabase(this.DataBaseName,
context.MODE_PRIVATE, null);
createTabel();
Log.v(this.TAG, "create or Open DataBase。。。");
}
}
public void close() {
db.close();
}
}
package com.topsun;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.util.Log;
public class DBHelper {
private static final String TAG = "UserDB_DBHelper.java";
private static final String DataBaseName = "UserDB";
SQLiteDatabase db;
Context context;
public DBHelper(Context context) {
this.open(context);
}
private void createTabel() {
// TODO Auto-generated method stub
String sql = "";
try {
sql = "CREATE TABLE IF NOT EXISTS TestUser (ID INTEGER PRIMARY KEY autoincrement, NAME TEXT, SEX TEXT, AGES INTEGER)";
this.db.execSQL(sql);
Log.v(TAG, "Create Table TestUser ok");
} catch (Exception e) {
Log.v(TAG, "Create Table TestUser fail");
} finally {
//this.db.close();
Log.v(TAG, "Create Table TestUser ");
}
}
public boolean save(String name, String sex, Integer ages) {
String sql = "insert into TestUser values(null,'" + name + "','" + sex
+ "'," + ages + ")";
try {
this.db.execSQL(sql);
Log.v(TAG, "insert Table TestUser 1 record ok");
return true;
} catch (Exception e) {
Log.v(TAG, "insert Table TestUser 1 record fail");
return false;
} finally {
//this.db.close();
Log.v(TAG, "insert Table TestUser ");
}
}
public Cursor loadAll() {
Cursor cur = db.query("TestUser", new String[] { "ID", "NAME","SEX","AGES"}, null,
null, null, null, null);
return cur;
}
public void open(Context context){
if (null == db || !this.db.isOpen()){
this.context = context;
this.db = context.openOrCreateDatabase(this.DataBaseName,
context.MODE_PRIVATE, null);
createTabel();
Log.v(this.TAG, "create or Open DataBase。。。");
}
}
public void close() {
db.close();
}
}