AScript 1.2.4

AScript

相关文章

• AScript轻量级动态脚本引擎
• AScript如何实现中文脚本引擎
• AScript扩展多种脚本语言
• AScript函数体系详解
• AScript之eval函数详解
• 基于AScript的python3脚本语言发布啦！
• AScript中一个很有意思的语法
• AScript之匿名类型与动态类型
• AScript如何实现LINQ语法

介绍

C#动态脚本解析编译执行引擎

• 支持注入变量
• 支持定义变量
• 支持注入函数
• 支持定义函数
• 支持注入类型
• 支持LINQ语法、Lambda表达式
• 支持元组类型、匿名类型、动态类型
• 支持事件处理
• 支持16进制整数表示：0x0A
• 支持多语句：用分号分隔多条语句
• 支持行注释：// 行注释
• 支持块注释：/* 块注释 */
• 支持if/else语句
• 支持for/while/foreach语句
• 支持continue/break/return
• 支持自定义语法解析（自定义关键字）
• 支持流式读取表达式
• 支持自定义语言环境，默认已实现CSharpLang
• 支持2种执行模式：

1. 解析执行：解析过程中计算结果，对于非循环语句有较高的性能及低内存，有循环语句则建议使用第2种编译执行方式

var script = new Script();
var result = script.Eval("5+8*6");
Assert.AreEqual(53, result);

2. 编译执行：解析过程中构建Expression表达式树，编译结果可缓存，对于执行频率高的表达式建议使用编译缓存方式执行，提高性能

// 方式1
var script = new Script();
var result = script.Eval("5+8*6", ECompileMode.All);
// 方式2
var script = new Script();
script.Options.CompileMode = ECompileMode.All;
var result = script.Eval("5+8*6");
// 方式3（缓存）
var script = new Script();
// -1表示缓存时间为永久缓存
var result = script.Eval("5+8*6", -1);

• 上下文环境会缓存临时变量及函数，编译执行模式可关闭该缓存（获得更高的性能）

var script = new Script();
script.Options.CompileMode = ECompileMode.All;
//script.Options.RewriteVariables = false;
//script.Options.RewriteFunctions = false;
script.Eval("int sum(int a, int b)=>a+b;int n=10;sum(n,5)");
script.Eval("n+6"); // 如果RewriteVariables为false，则抛异常变量n不存在
script.Eval("sum(10,20)"); // 如果RewriteFunctions为false，则抛异常函数sum不存在
var sum = script.Context.GetFunc<int, int, int>("sum");
int result = sum(10, 20);

安装

install-package AScript

使用说明

• 命名空间：using AScript;
• 已内置C#常用数据类型，如：int/bool/string/long/double/DateTime等
• 已内置Convert数据转换方法，使用示例：'12'.ToInt32() 等同于 ToInt32('12') 或者 Convert.ToInt32('12')

注入类型及类型中的方法

var script = new Script();
script.Context.AddType<Person>();
script.Eval("var p1 = new Person('tom', 20); p1.SayHello()"); // Hello, my name is tom, I'm 20 years old
script.Eval("var p2 = Person.Create('john', 35); p2.SayHello()"); // Hello, my name is john, I'm 35 years old

// 添加类中的所有公开静态方法
script.Context.AddFunc<Person>();
script.Eval("var p3 = Create('jim', 15); p3.SayHello()"); // Hello, my name is jim, I'm 15 years old
// 添加类中的所有公开实例方法
var p = new Person("san", 27);
script.Context.AddFunc(p);
script.Eval("SayHello()"); // Hello, my name is san, I'm 27 years old

public class Person
{
	public string Name { get; set; }
	public int Age { get; set; }

	public event EventHandler<EventArgs> Saying;

	public Person() { }
	public Person(string name, int age)
	{
		this.Name = name;
		this.Age = age;
	}
	
	protected virtual void OnSaying(EventArgs e)
	{
		this.Saying?.Invoke(this, e);
	}

	public string SayHello()
	{
		OnSaying(EventArgs.Empty);
		return $"Hello, my name is {this.Name}, I'm {this.Age} years old";
	}

	public static Person Create(string name, int age)
	{
		return new Person(name, age);
	}
}

变量

var script = new Script();
script.Context.SetVar("m", 6);
var result = script.Eval("int n=8;n+m+10*(3+0x0A)");
Assert.AreEqual(8 + 6 + 10 * (3 + 0x0A), result);

匿名类型

string s = @"
var a = new { Name='tony', Age=20 }
a.Name + ':' + a.Age
";
var script = new Script();
Assert.AreEqual("tony:20", script.Eval(s));
var a = script.Eval("a");
// 获取脚本中定义的匿名类型
var type = Script.AnonymousTypes.CreateType(new[] { "Name", "Age" }, new[] { typeof(string), typeof(int) });
Assert.IsInstanceOfType(a, type);
dynamic d = a;
Assert.AreEqual("tony", d.Name);
Assert.AreEqual(20, d.Age);
Assert.AreEqual("{ Name = tony, Age = 20 }", a.ToString());

动态类型

string s = @"
var a = new ExpandoObject();
a.Name = 'jim';
a.Age = 23;
a
";
var script = new Script();
dynamic a = script.Eval(s);
Assert.IsInstanceOfType(a, typeof(ExpandoObject));
Assert.AreEqual("jim", a.Name);
Assert.AreEqual(23, a.Age);

类型转换

string s = "int n = 10; n+(long)n";
var script = new Script();
var r = script.Eval(s, out var type);
Assert.AreEqual(20L, r);
Assert.AreEqual(typeof(long), type);

注入函数

var script = new Script();
script.Context.AddFunc<int, int, int>("sum", (a, b) => a + b);
script.Context.AddFunc<int, int, int, int>("sum", (a, b, c) => a + b + c);
script.Context.AddFunc<int, int, int>("mult", (a, b) => a * b);
Assert.AreEqual(1+2+8+1+2+3+5*6, script.Eval("sum(1,2)+8+sum(1,2,3)+mult(5,6)"));

自定义函数

string s = @"
int exec(int a, int b) {
	var n=mult(a,10);
	n+b;
}
// 2个数相加
int sum(int a, int b)=>a+b;
// 3个数相加
int sum(int a, int b, int c)=>a+b+c;
// 乘法
int mult(int a, int b)=>a*b;
/* 
调用函数计算结果：
1 + 2 + 8 + 1 + 2 + 3 + 5 * 6
*/
sum(1,2)+8+sum(1,2,3)+mult(5,6)
";
var script = new Script();
var result = script.Eval(s);
Assert.AreEqual(1 + 2 + 8 + 1 + 2 + 3 + 5 * 6, result);
Assert.AreEqual(1 + 2 + 8, script.Eval("sum(1,2)+8"));
Assert.AreEqual(5 * 10 + 2 + 8, script.Eval("exec(5,2)+8"));

递归

string s = @"
int exec(int a) {
	if (a < 1) return 0;
	a + exec(a-1);
}
exec(5)
";
var script = new Script();
Assert.AreEqual(15, script.Eval(s));
Assert.AreEqual(55, script.Eval("exec(10)"));

事件

示例1：

var s = @"
var p = new Person('tom', 20);
p.Saying += (ss,ee)=>{
	(ss as Person).Age+=1;
}
p.SayHello();
p.SayHello();
";
var script = new Script();
script.Context.AddType<Person>();
Assert.AreEqual("Hello, my name is tom, I'm 22 years old", script.Eval(s));

示例2：

var s = @"
void saying(object sender, EventArgs e) {
	(sender as Person).Age+=1;
}
var p = new Person('tom', 20);
p.Saying += saying;
p.SayHello();
p.Saying -= saying;
p.SayHello();
";
var script = new Script();
script.Context.AddType<Person>();
Assert.AreEqual("Hello, my name is tom, I'm 21 years old", script.Eval(s));

示例3：

var s = @"
void saying(object sender, EventArgs e) {
	(sender as Person).Age+=1;
}
var p = new Person('tom', 20);
p.Saying += saying;
p.SayHello();
p.SayHello();
";
var script = new Script();
script.Context.AddType<Person>();
Assert.AreEqual("Hello, my name is tom, I'm 22 years old", script.Eval(s));
var p = script.Eval<Person>("p");
Assert.AreEqual("Hello, my name is tom, I'm 23 years old", p.SayHello());
var handle = script.Context.GetEvent<EventHandler<EventArgs>>("saying");
p.Saying -= handle;
Assert.AreEqual("Hello, my name is tom, I'm 23 years old", p.SayHello());

字符串插值

string s = "var name='tom'; $'hello {name}, 5+8={5+8}'";
var script = new Script();
Assert.AreEqual("hello tom, 5+8=13", script.Eval(s));

字符串索引和截取

var script = new Script();
Assert.AreEqual('e', script.Eval("'hello'[1]"));
Assert.AreEqual('e', script.Eval("'hello'[-4]"));
Assert.AreEqual("ell", script.Eval("'hello'[1:4]"));
Assert.AreEqual("ell", script.Eval("'hello'[-4:-1]"));

数组

var script = new Script();
var result1 = (List<int>)script.Eval("var arr1 = [0,1,2,3,4]; arr1[1:4]");
var result2 = (List<int>)script.Eval("var arr2 = [0,1,2,3,4]; arr2[-4:-1]");
CollectionAssert.AreEqual(new List<int> { 1, 2, 3 }, result1);
CollectionAssert.AreEqual(new List<int> { 1, 2, 3 }, result2);
Assert.AreEqual(1, script.Eval("arr1[1]"));
Assert.AreEqual(1, script.Eval("arr1[-4]"));

点操作符

var script = new Script();
Assert.AreEqual(DateTime.Now.Year, script.Eval("DateTime.Now.Year"));
Assert.AreEqual(int.MaxValue, script.Eval("int.MaxValue"));
Assert.AreEqual("hello".Length, script.Eval("'hello'.Length"));
Assert.AreEqual("hello".Substring(1, 2), script.Eval("'hello'.Substring(1, 2)"));

for

string s = @"
int total=0;
for(var i=1; i<=10; i++) {
	total += i;
}
total";
var script = new Script();
Assert.AreEqual(55, script.Eval(s));

foreach

string s = @"
int n=0;
var list = new int[] { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12 };
foreach(var item in list)
{
	if (item % 2 == 0) continue;
	if (item >10) break;
	n+=item;
}
n";

var script = new Script();
Assert.AreEqual(25, script.Eval(s));
// 编译缓存方式执行
Assert.AreEqual(25, script.Eval(s, -1));

while

string s = @"
int total=0;
int n = 1;
while(n <= 10) {
	total += n;
	n++;
}
total";
var script = new Script();
Assert.AreEqual(55, script.Eval(s));

LINQ

string s = @"
var persons = new[] { new Person(""tom"", 20), new Person(""jim"", 25), new Person(""san"", 18), new Person(""kit"", 25) }.AsQueryable();
var q = from a in persons
		group a by a.Age into g
		select new { g.Key, Count = g.Count() };
q.ToList()
";
var script = new Script();
script.Context.AddType<Person>();
var list = script.Eval<IList>(s);
Assert.AreEqual(3, list.Count);
dynamic d0 = list[0];
Assert.AreEqual(20, d0.Key);
Assert.AreEqual(1, d0.Count);
dynamic d1 = list[1];
Assert.AreEqual(25, d1.Key);
Assert.AreEqual(2, d1.Count);
dynamic d2 = list[2];
Assert.AreEqual(18, d2.Key);
Assert.AreEqual(1, d2.Count);

Queryable扩展方法

Queryable中的扩展方法，包含Where/Select/OrderBy/Skip/Take/FirstOrDefault/SelectMany/Join等等。

string s = @"
var q = [1,2,3,4,5].AsQueryable();
var r = q.Where(a=>a%2==0).ToList();
";
var script = new Script();
var r = script.Eval(s);
Assert.IsInstanceOfType(r, typeof(List<int>));
Assert.AreEqual("2,4", string.Join(',', (List<int>)r));

Enumerable扩展方法

Enumerable中的扩展方法，包含Where/Select/OrderBy/Skip/Take/FirstOrDefault/SelectMany/Join等等。

string s = @"
var r = [1,2,3,4,5].Where(a=>a%2==0).ToList();
";
var script = new Script();
var r = script.Eval(s);
Assert.IsInstanceOfType(r, typeof(List<int>));
Assert.AreEqual("2,4", string.Join(',', (List<int>)r));

static语句

static语句是在编译期间进行解析执行，即static语句不参与编译，而是直接执行结果。 注意：static语句中使用的变量也必须在static语句中定义的，否则报错变量不存在。

var s = @"
static int n = 10; // 直接执行，不参与编译
static x = n * 2; // 直接执行，不参与编译
int y = static n * 2; // 编译结果：y = 20
/*
int m=20;
int a = static m * 2; // 报错：variable m is not exists
*/
int z = n * 2; // 编译结果：z = n * 2
x+y+z;
";
var script = new Script();
// 编译
var func = script.Compile<int>(s);
Assert.AreEqual(10, script.Context.EvalVar("n"));
Assert.AreEqual(20, script.Context.EvalVar("x"));
Assert.IsNull(script.Context.EvalVar("y"));
Assert.IsNull(script.Context.EvalVar("z"));
// 执行
Assert.AreEqual(60, func());

自定义语法解析

• 注：自定义语法解析需要谨慎处理，否则会破坏后续语法解析，导致脚本执行异常或者执行结果不符合预期。

string s = @"
int n=0;
var list = new int[] { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12 };
foreach(var item in list)
{
	if (item % 2 == 0) 继续;
	if (item >10) 中断;
	n+=item;
}
n";

var script = new Script();
script.Context.AddTokenHandler("继续", ContinueTokenHandler.Instance);
script.Context.AddTokenHandler("中断", BreakTokenHandler.Instance);
Assert.AreEqual(25, script.Eval(s));

多脚本语言

脚本中使用#lang/#end或者@lang/@end语法嵌入其他语言，如果没有#end/@end，则表示后面的脚本都指定该语言执行。 如果要嵌入python语言，请使用@lang/@end，因为#是python中的注释语句，#lang/#end会失效。

string s = @"
int n=10;
#lang 中文
整型 m=20;
#end
m+n";
var script = new Script();
Assert.AreEqual(30, script.Eval(s));

编译

var script = new Script();
//var func = script.Compile<int, int, int>("a+b*2", "a", "b");
var func = script.Compile<Func<int, int, int>>("a+b*2", new[] { "a", "b" });
Assert.IsNotNull(func);
Assert.AreEqual(11, func(3, 4));

Lambda

脚本生成Lambda表达式，应用场景：脚本->LINQ

var script = new Script();
var whereCondition = script.Lambda<Person, bool>("p.Name=='tom' || p.Name=='jim'", "p");
IQueryable<Person> query = ...;
var list = query.Where(whereCondition).ToList();