SQLite Helper (C#) z
http://www.codeproject.com/Articles/746191/SQLite-Helper-Csharp
Introduction
I have written a small class, SQLiteHelper which aims to simplify the usage of SQLite in C#.
Prerequisite
This small class is built on top of System.Data.SQLite.DLL. A reference of this DLL must be added into your projects.
Download: https://system.data.sqlite.org
List of Simplified Functions
- GetTableStatus
- GetColumnStatus
- CreateTable
- BeginTransaction, Commit, Rollback
- Select
- Execute
- ExecuteScalar
- ExecuteScalarStr
- ExecuteScalarInt
- ExecuteScalarDateTime
- ExecuteScalarDecimal
- ExecuteScalarBlob
- Escape
- Insert
- Update
- RenameTable
- CopyAllData
- DropTable
Getting Start
Add this using statement at the top of your class:
using System.Data.SQLite;
SQLiteConnection
and SQLiteCommand
have to be initialized before using SQLiteHelper
:
Example:
using (SQLiteConnection conn = new SQLiteConnection("data source=C:\\data"))
{
using (SQLiteCommand cmd = new SQLiteCommand())
{
cmd.Connection = conn;
conn.Open(); SQLiteHelper sh = new SQLiteHelper(cmd); // do something... conn.Close();
}
}
1. GetTableStatus
Get all information of tables in the database.
DataTable dt = sh.GetTableStatus();
2. GetColumnStatus
Get all information of columns in specific table.
// Get column's information from table "person"
DataTable dt = sh.GetColumnStatus("person");
3. CreateTable
Create table.
Example table structure: Person
Column Name | Data Type | Primary Key | Not Null | Default Value |
id | int | true | ||
name | text | |||
membershipid | int | |||
level | decimal | 5.5 |
SQLiteTable tb = new SQLiteTable("person"); tb.Columns.Add(new SQLiteColumn("id", true));
tb.Columns.Add(new SQLiteColumn("name"));
tb.Columns.Add(new SQLiteColumn("membershipid", ColType.Integer));
tb.Columns.Add(new SQLiteColumn("level", ColType.Decimal, false, false, "5.5")); sh.CreateTable(tb);
4. BeginTransaction, Commit, Rollback
Applying transactions.
sh.BeginTransaction(); try
{
// execute some queries sh.Commit();
}
catch
{
sh.Rollback();
}
5. Select
Return the query result in DataTable format.
DataTable dt = sh.Select("select * from person order by id;");
6. Execute
Execute single SQL query.
sh.Execute("insert into person(name)values('hello');");
7. ExecuteScalar
Return the result from first row first column in object format.
object ob = sh.ExecuteScalar("select max(id) from person;");
8. ExecuteScalarStr
Return the result from first row first column in string format.
string s = sh.ExecuteScalarStr("select max(id) from person;");
9. ExecuteScalarInt
Return the result from first row first column in Int format.
int i = sh.ExecuteScalarInt("select max(id) from person;");
10. ExecuteScalarDateTime
Return the result from first row first column in DateTime format.
DateTime date = sh.ExecuteScalarDateTime("select dateregister from person where id = 1;");
11. ExecuteScalarDecimal
Return the result from first row first column in decimal format.
decimal d = sh.ExecuteScalarDecimal("select level from person where id = 1;");
12. ExecuteScalarBlob
Return the result from first row first column in byte[] format.
byte[] ba = sh.ExecuteScalarBlob("select photo from person where id = 1;");
13. Escape
Escape string sequence for text value to avoid SQL injection or invalid SQL syntax to be constructed.
string value = sh.Escape(input);
14. Insert
Insert data.
Sample 1: Insert single row.
var dic = new Dictionary<string, object>();
dic["name"] = "John";
dic["membershipid"] = 1;
dic["level"] = 6.8; sh.Insert("person", dic);
Sample 2: Insert multiple rows.
var lst = new List<Dictionary<string,>(); var dic1 = new Dictionary<string,>();
dic1["name"] = "John";
dic1["membershipid"] = 1;
dic1["level"] = 6.8;
lst.Add(dic1); var dic2 = new Dictionary<string,>();
dic2["name"] = "Catherine";
dic2["membershipid"] = 2;
dic2["level"] = 9.7;
lst.Add(dic2); var dic3 = new Dictionary<string,>();
dic3["name"] = "Thomas";
dic3["membershipid"] = 3;
dic3["level"] = 8.6;
lst.Add(dic3); sh.Insert("person", lst);
16. Update
Update row.
Sample 1: Update with single condition (where id = 1)
var dicData = new Dictionary<string, object>();
dicData["name"] = "no name";
dicData["membershipid"] = 0;
dicData["level"] = 5.5; sh.Update("person", dicData, "id", 1);
Sample 2: Update with multiple condition (where membership = 1 and level = 5.5)
var dicData = new Dictionary<string, object>();
dicData["name"] = "no name";
dicData["status"] = 0;
dicData["money"] = 100;
dicData["dateregister"] = DateTime.MinValue; var dicCondition = new Dictionary<string,>();
dicCondition["membershipid"] = 1;
dicData["level"] = 5.5; sh.Update("person", dicData, dicCondition);
16. RenameTable
Rename a table.
sh.RenameTable("person", "person_backup");
17. CopyAllData
Copy all data from one table to another.
sh.CopyAllData("person", "person_new");
Before copying, SQLiteHelper
will scan the two tables for match columns. Only columns that exist in both tables will be copied.
18. DropTable
Drop table, delete a table
sh.DropTable("person");
That's it, guys/girls. Comments are welcome.
Happy coding
Also available at: https://sh.codeplex.com/[^]
SQLite Helper (C#) z的更多相关文章
- sqlite helper
//-------------------------------------------------------------------------- // // Copyright (c) BUS ...
- SQLite Helper (C#) zt
http://www.codeproject.com/Articles/746191/SQLite-Helper-Csharp This small class (SQLiteHelper.cs) i ...
- C#操作SQLite数据库
SQLite介绍 SQLite is a software library that implements a self-contained, serverless, zero-configurati ...
- Android中多表的SQLite数据库(译)
原文: Android SQLite Database with Multiple Tables 在上一篇教程Android SQLite Database Tutorial中,解释了如何在你的And ...
- C# SQLite 创建数据库的方法增删查改语法和命令
SQLite介绍 SQLite是一个开源.免费的小型RDBMS(关系型数据库),能独立运行.无服务器.零配置.支持事物,用C实现,内存占用较小,支持绝大数的SQL92标准. SQLite数据库官方主页 ...
- 安卓APP与智能硬件相结合的简易方案
第1章 概 述 (作者小波QQ463431476) (来源http://blog.chinaaet.com/zhaocundang/p/5100017645博客) (来源 http://www. ...
- HRPlugin For Xcode发布(附源码地址)
今天给大家介绍的这个插件,是我在IOS平台上开发以来,一些想法的集合体.因为本人时常感觉在开发过程中无论从GOOGLE资料查找和SQL数据库查询,正则表达式测试,SVN等,这些经常要做的操作中,耽误了 ...
- 学习笔记:调用js文件冲突问题解决方案
之前自己动手做了一个小网站,在实现过程中遇到了一个关于js文件调用冲突的问题. 具体问题描述如下:在index.html文件中引用了两个js文件,单独添加banner.js或者focus_pic.js ...
- 使用Rxjava缓存请求
最近,我尝试使用RxJava开发了一款闲时备份app.我必须承认,一旦你get到了正确的方式,RxJava几乎感觉就像作弊.一切看起来更简洁,多个请求能够被组合,且非常容易控制.通过在UI线程观察和在 ...
随机推荐
- Android代码中动态设置图片的大小(自动缩放),位置
项目中需要用到在代码中动态调整图片的位置和设置图片大小,能自动缩放图片,用ImageView控件,具体做法如下: 1.布局文件 <RelativeLayout xmlns:android=&qu ...
- css z-index详解
写css z-index的时候经常会出现很多莫名其妙的问题,下面对z-index属性做彻底的剖析,本文参考了<一个css中z-index的用法>,并做了很多demo,方便了解z-index ...
- android87 Service
---------------------------------------------------------------------------- #Service(服务和Activity是运行 ...
- Qt之QtScript(一)
C++和JavaScript相互通信.今天就学习QtScript模块吧. Qt 包含完全集成的 ECMA 标准脚本引擎.Qt Script 集成了 QObject,为脚本提供了 Qt 的信号与槽 (S ...
- Java基础知识强化之IO流笔记50:IO流练习之 复制多级文件夹的案例
1. 复制多级文件夹的案例 需求:复制多级文件夹 数据源:E:\JavaSE\day21\code\demos 目的地:E:\ 分析: A:封装数据源File ...
- Java实现希尔排序(增量递减排序)
package Insert.sort; import java.util.Scanner; /*又叫缩小增量排序,本质是插入排序,将待排的序列增量分成几个子序列,分别对每个子序列进行直接插入排序 * ...
- Java8特性---关于Null
为了防止无良网站的爬虫抓取文章,特此标识,转载请注明文章出处.LaplaceDemon/SJQ. http://www.cnblogs.com/shijiaqi1066/p/5713941.html ...
- ZooKeeper 分布式锁实现
1 场景描述 在分布式应用, 往往存在多个进程提供同一服务. 这些进程有可能在相同的机器上, 也有可能分布在不同的机器上. 如果这些进程共享了一些资源, 可能就需要分布式锁来锁定对这些资源的访问. 2 ...
- NC portal怎么重新开始入门,整个配置过程包括配置一个节点
有一份文档,之后会上传,暂时不上传
- DataContext 数据在F5刷新频繁,会出现数据读取错误
DataContext 数据在F5刷新频繁,会出现数据读取错误 DataContext是 Linq to sql数据模型的底层数据库对象所有LInq数据表对象都是由它派生的, 只要建立一个数据库操作, ...