C# 如何使用/理解lambda表达式？

我有以下方法：

private byte[] GetEmailAsBytes(string lstrBody)
{
   byte[] lbytBody;
   ASCIIEncoding lASCIIEncoding = new ASCIIEncoding();
   lbytBody = lASCIIEncoding.GetBytes(lstrBody);
   return lbytBody;
}

我想知道这是否可以转换为lambda表达式。我是新来的。我试过：

Func<string> BodyToBytes = x => {
        ASCIIEncoding lASCIIEncoding = new ASCIIEncoding();
        return lASCIIEncoding.GetBytes(x);
}

但这并不适用于编译。我只是想将字符串转换为一系列字节，出于兴趣，我想使用lambda表达式来实现这一点。

表达式Func相当于一个不接受参数并返回字符串的函数

您的示例显然返回一个字节[]，但您希望它接受一个字符串并返回一个字节[]

要解决此问题，请将BodyToBytes更改为与以下内容匹配。请注意，参数的类型首先是逗号分隔的，然后是返回类型。在这种情况下，x将是string类型

有关引用，请参阅或。

表达式Func相当于不接受任何参数并返回字符串的函数

您的示例显然返回一个字节[]，但您希望它接受一个字符串并返回一个字节[]

要解决此问题，请将BodyToBytes更改为与以下内容匹配。请注意，参数的类型首先是逗号分隔的，然后是返回类型。在这种情况下，x将是string类型

---

如需参考，请参阅或。

我已编写了一个NUnit示例，以供个人理解

    private class ld
    {
        public Boolean make<T>(T param, Func<T, bool> func) 
        {
            return func(param);
        }
    }

    private class box
    {
        public Boolean GetTrue() { return true; }
        public int Secret = 5;
    }

    [Test]
    public void shouldDemonstrateLambdaExpressions()
    {
        //Normal Boolean Statement with integer
        int a = 5;
        Assert.IsTrue(a == 5);
        Assert.IsFalse(a == 4);

        //Boolean Statement Expressed Via Simple Lambda Expression
        Func<int, bool> myFunc = x => x == 5;
        Assert.IsTrue(myFunc(5));
        Assert.IsFalse(myFunc(4));

        //Encapsuled Lambda Expression Called on Integer By Generic Class with integer
        ld t = new ld();
        Assert.IsTrue(t.make<int>(5,myFunc));
        Assert.IsFalse(t.make<int>(4, myFunc));

        //Encapsuled Lambda Expression Called on Integer By Generic Class with implicit Generics
        Assert.IsTrue(t.make(5, myFunc));

        //Simple Lambda Expression Called on Integer By Generic Class with implicit Generic
        Assert.IsTrue(t.make(20, (x => x == 20)));
        Assert.IsTrue(t.make(20, (x => x > 12)));
        Assert.IsTrue(t.make(20, (x => x < 100)));
        Assert.IsTrue(t.make(20, (x => true)));

        //Simple Lambda Expression Called on a Class By Generic Class with implicit Generic 
        //FULL LAMBDA POWER REACHED
        box b = new box();
        Assert.IsTrue(t.make(b, (x => x.GetTrue())));
        Assert.IsTrue(t.make(b, (x => x.Secret == 5)));
        Assert.IsFalse(t.make(b, (x => x.Secret == 4)));
    }

---

为了我个人的理解，我写了一个NUnit的例子

    private class ld
    {
        public Boolean make<T>(T param, Func<T, bool> func) 
        {
            return func(param);
        }
    }

    private class box
    {
        public Boolean GetTrue() { return true; }
        public int Secret = 5;
    }

    [Test]
    public void shouldDemonstrateLambdaExpressions()
    {
        //Normal Boolean Statement with integer
        int a = 5;
        Assert.IsTrue(a == 5);
        Assert.IsFalse(a == 4);

        //Boolean Statement Expressed Via Simple Lambda Expression
        Func<int, bool> myFunc = x => x == 5;
        Assert.IsTrue(myFunc(5));
        Assert.IsFalse(myFunc(4));

        //Encapsuled Lambda Expression Called on Integer By Generic Class with integer
        ld t = new ld();
        Assert.IsTrue(t.make<int>(5,myFunc));
        Assert.IsFalse(t.make<int>(4, myFunc));

        //Encapsuled Lambda Expression Called on Integer By Generic Class with implicit Generics
        Assert.IsTrue(t.make(5, myFunc));

        //Simple Lambda Expression Called on Integer By Generic Class with implicit Generic
        Assert.IsTrue(t.make(20, (x => x == 20)));
        Assert.IsTrue(t.make(20, (x => x > 12)));
        Assert.IsTrue(t.make(20, (x => x < 100)));
        Assert.IsTrue(t.make(20, (x => true)));

        //Simple Lambda Expression Called on a Class By Generic Class with implicit Generic 
        //FULL LAMBDA POWER REACHED
        box b = new box();
        Assert.IsTrue(t.make(b, (x => x.GetTrue())));
        Assert.IsTrue(t.make(b, (x => x.Secret == 5)));
        Assert.IsFalse(t.make(b, (x => x.Secret == 4)));
    }