Android SQLiteOpenHelper

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package com.achilies.yuqingxitong.util;

import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;

public class DBHelper extends SQLiteOpenHelper {
	private static final String DB_NAME = "yuqing.db";
	private static final String WARN = "t_warn";
	// 创建SQL语句
	private static final String warnSql = " CREATE TABLE t_warn (_ID INTEGER PRIMARY KEY autoincrement,u_aid INTEGER,u_level INTEGER,u_title text,u_url text,u_site text,u_tmpost text,u_content text)";
	// SQLiteDatabase实例
	private SQLiteDatabase db;

	public DBHelper(Context context) {
		super(context, DB_NAME, null, 1);

	}

	@Override
	public void onCreate(SQLiteDatabase db) {
		db.execSQL(warnSql);
	}

	// 打开数据库
	public void open() {
		db = getWritableDatabase();
	}

	@Override
	public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
		// TODO Auto-generated method stub
		String sql = "DROP TABLE IF EXISTS " + WARN;
		db.execSQL(sql);
		onCreate(db);
	}

	public void dropTable(String tableName) {
		String sql = "DROP TABLE IF EXISTS " + WARN;
		db.execSQL(sql);
	}

	public void createTable(String tableName) {
		db.execSQL(warnSql);
	}

	// 插入方法
	public void insert(ContentValues values, String tableName) {
		db.insert(tableName, null, values);
	}

	// 查询方法
	public Cursor query(String tableName) {
		Cursor c = db.query(tableName, null, null, null, null, null, "_ID asc");
		return c;
	}

	// 查询方法
	public Cursor queryByName(String name) {
		Cursor c = db.query(WARN, null, "u_title=?", new String[] { name },
				null, null, "_ID desc");
		return c;
	}

	// 修改
	public void updata(ContentValues values, String name) {
		db.update(WARN, values, "u_title=?", new String[] { name });
	}

	// 删除方法
	public void del(String u_username) {
		db.delete(WARN, "u_title=?", new String[] { u_username });
	}

	// 关闭数据库
	public void close() {
		if (db != null) {
			db.close();
		}
	}
}

使用：

DBHelper dbHelper = new DBHelper(context);
dbHelper.open();
dbHelper.del(dataList.get(cur).getTitle());
dbHelper.close();