c# - C#中的字符串结尾

Question

字符串存入内存时是否以\0字符结尾？编译器如何知道结束？？

如果是真的

Console.WriteLine(str.LastIndexOf('\0'));

必须返回长度，但输出为= -1

Answer 1

来自 MSDN

Internally, the text is stored as a sequential read-only collection of Char objects. There is no null-terminating character at the end of a C# string; therefore a C# string can contain any number of embedded null characters ('\0').

此外，来自 Jon Skeet 的 Strings in .NET and C#

Although strings aren't null-terminated as far as the API is concerned, the character array is null-terminated, as this means it can be passed directly to unmanaged functions without any copying being involved, assuming the inter-op specifies that the string should be marshalled as Unicode.

简而言之，内部字符数组确实以 \0 结尾，但 API(例如，LastIndexof)会忽略它。

此外，如果您手动插入 \0 在 c# 字符串的中间(例如，Hello\0World)，C# 字符串API 会忽略它，但其他 API 可能不会并最终忽略第一个 \0 之后的所有内容(例如，World)。

查看 reference source

public override int GetHashCode() {
    //...
    Contract.Assert(src[this.Length] == '\0', "src[this.Length] == '\\0'");
    //...
}