标签：roo 性能 tde root lin highlight using 数据 enc
该项目内置单表linq操作，xml动态sql解析，词法分析，类型映射等功能。
SqlMapper,用来处理sql与数据库操作，它设计的目标是支持mysql,sqlserver,sqllite,pgsql等.
TypeMapper用于完成将数据库的字段类型映射到C#类型，内部定义了类型转换函数和转换规则.
TypeConvert用于完成数据库记录到C#类型的转换。通过IL动态创建IDataReader对象到C#实体类的转换函数和将C#对象解构成Key-value的函数.
ExpressionContext是一个轻量的词法分析器，用于将字符串表达式生成C#表达式，进而生成委托.
该类型的实例是线程安全的，可复用的。它的设计及其简单，功能也很有限，但是对于我们的需求足够了. 它的实现逻辑如下：
var expr = "(Age!=null) && (Name==‘zs‘)";
/**
1.通过正则匹配出每一个括号，因此你必须手动的给每个二元表达式加括号，它无法识别运算符的优先级.
$1 = (Age!=null)
$2 = (Name==‘zs‘)
$3 = $1 && $2
2.创建参数类型
Expression.Parameter(typeof(T), "p");
3.逐个创建二元表达式
Expression.MakeUnary(ExpressionType.Convert, expr, type)
...
*/
var context = new ExpressionContext();
//Age必须是可以为null的类型:int?
var result = context.Create<Student>("(Age != null) && (Name==‘zs‘)");
var flag= result.Func(new Student { Age = 1, Name = "zs" });
/**
常见错误:
1. (Age != null) && Name==‘zs‘
2. public class Student{ public int Age{get;set;} public string Name {get;set;}}
*/
var context = new ExpressionContext();
var result = context.Create<Student>("(Age!=null)&&(Name==‘zs‘)");
var expr = result.LambdaExpression;
Func<Student, bool> func = result.Func;
var flag = func(new Student { Age = 1, Name = "zs" });
<?xml version="1.0" encoding="utf-8" ?> <commands namespace="sutdent"> <!-- 框架只定义了if,variable,where等标签 insert,select可以随意，并没有实际意义 --> <variable id="columns"> Id,Age,Name </variable> <select id="list-dynamic"> select ${columns} from student <where> <if test="id=@Id"/> </where> limit 0,1 </select> <insert id="add"> insert into student(name,age)values(@Name,@age) </insert> </commands>
//for xml query
var resovle = new XmlResovle();
resovle.Load(@"E:\SqlBatis\SqlBatis.Test", "*.xml");
//普通sql
var sql1 = resovle.Resolve("namespace.id");
//动态sql
var sql2 = resovle.Resolve("namespace.id",new { Id=(int?)null,Age=2});
public class MysqlDbConrext : DbContext
{
public IDbQuery<Student> Students { get => new DbQuery<Student>(this); }
private static readonly IXmlResovle resovle;
static MysqlDbConrext()
{
//不要为每一个DbContext加载配置
resovle = new XmlResovle();
resovle.Load(@"E:\SqlBatis\SqlBatis.Test","*.xml");
}
protected override void OnLogging(string message, object parameter = null, int? commandTimeout = null, CommandType? commandType = null)
{
}
protected override DbContextBuilder OnConfiguring(DbContextBuilder builder)
{
ILoggerFactory factory = LoggerFactory.Create(b => { b.AddConsole(); b.AddDebug(); b.SetMinimumLevel(LogLevel.Debug); });
builder.Connection = new MySql.Data.MySqlClient.MySqlConnection("server=127.0.0.1;user id=root;password=1024;database=test;");
builder.XmlResovle = null;
return builder;
}
public MysqlDbConrext()
{
Students = new DbQuery<Student>(this);
}
}
var db = new DbContext(new DbContextBuilder()
{
DbContextType=DbContextType.Mysql,
...
});
using (var db = new SqlDbContext())
{
//linq
var row = db.Students.Delete();
var (list, count) = db.Students
.Page(1, 2)
.SelectMany();
//dynamic
var p = new { Id = (int?)null, Name = "zs" };
var dylist = db.Students
.Where(a => a.Id == 1, p.Id != null)
.Where(a => a.Name == p.Name, p.Name != null)
.SelectMany();
//xml
row = db.From("sutdent.add", new Student()
{
Age = 20,
IsDelete = true,
Name = "xml"
}).ExecuteNonQuery();
//dynamic：注意由于内部会缓存表达式创建的委托，因此同一个动态的xml命令不能用不同的参数去获取它
//建议如果获取的xml命令是动态的，则应保证整个项目只有一次获取的代码，或者使用同一种参数类型
row = db.From("stutdent.list-dynamic", p).ExecuteNonQuery();
//多结果集查询，xml方式同样支持
using (var muti = db.ExecuteMultiQuery("select * from student;select count(1) from student;"))
{
//第一个结果集
var list = muti.GetList<Student>();
//第二个结果集
var count = muti.Get<int>();
}
}
标签：roo 性能 tde root lin highlight using 数据 enc
原文地址：https://www.cnblogs.com/chaeyeon/p/12205267.html
