参考微软官方文档-特殊字符@,地址 https://docs.microsoft.com/zh-cn/dotnet/csharp/language-reference/tokens/verbatim
1、在变量名前加@,可以告诉编译器,@后的就是变量名。主要用于变量名和C#关键字重复时使用。
string[] @for = { "John", "James", "Joan", "Jamie" }; for (int ctr = 0; ctr < @for.Length; ctr++) { Console.WriteLine($"Here is your gift, {@for[ctr]}!"); } // The example displays the following output: // Here is your gift, John! // Here is your gift, James! // Here is your gift, Joan! // Here is your gift, Jamie!
2、在字符串前加@,字符串中的转义字符串将不再转义。例外:""仍将转义为",{{和}}仍将转义为{和}。在同时使用字符串内插和逐字字符串时,$要在@的前面
string filename1 = @"c:documentsfilesu0066.txt"; string filename2 = "c:\documents\files\u0066.txt"; Console.WriteLine(filename1); Console.WriteLine(filename2); // The example displays the following output: // c:documentsfilesu0066.txt // c:documentsfilesu0066.txt
3、类似于第一条,用于在命名冲突时区分两个特性名。特性Attribute自定义的类型名称在起名时应以Attribute结尾,例如InfoAttribute,之后我们可以用InfoAttribute或Info来引用它。但是如果我们定义了两个自定义特性,分别命名Info和InfoAttribute,则在使用Info这个名字时,编译器就不知道是哪个了。这时,如果想用Info,就用@Info,想用InfoAttribute,就把名字写全。
using System; [AttributeUsage(AttributeTargets.Class)] public class Info : Attribute { private string information; public Info(string info) { information = info; } } [AttributeUsage(AttributeTargets.Method)] public class InfoAttribute : Attribute { private string information; public InfoAttribute(string info) { information = info; } } [Info("A simple executable.")] // Generates compiler error CS1614. Ambiguous Info and InfoAttribute. // Prepend '@' to select 'Info'. Specify the full name 'InfoAttribute' to select it. public class Example { [InfoAttribute("The entry point.")] public static void Main() { } }