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Update docs on strings not being null-terminated #28470

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Update docs on strings not being null-terminated #28470

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2 changes: 1 addition & 1 deletion docs/csharp/programming-guide/strings/index.md
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Expand Up @@ -9,7 +9,7 @@ ms.assetid: 21580405-cb25-4541-89d5-037846a38b07
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# Strings (C# Programming Guide)

A string is an object of type <xref:System.String> whose value is text. Internally, the text is stored as a sequential read-only collection of <xref:System.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'). The <xref:System.String.Length%2A> property of a string represents the number of `Char` objects it contains, not the number of Unicode characters. To access the individual Unicode code points in a string, use the <xref:System.Globalization.StringInfo> object.
A string is an object of type <xref:System.String> whose value is text. Internally, the text is stored as a sequential read-only collection of <xref:System.Char> objects. The <xref:System.String.Length%2A> property of a string represents the number of `Char` objects it contains, not the number of Unicode characters. To access the individual Unicode code points in a string, use the <xref:System.Globalization.StringInfo> object. The length of a C# string is stored in a dedicated field and it is not computed by iterating on the string data to find a null-terminator. Therefore, a C# string can contain any number of embedded null characters ('\0'). Note that C# strings are not just length-prefixed, but also internally null-terminated: this makes it safe to marshal them to native code expecting a null-terminated sequence of characters.
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@stephentoub stephentoub Mar 3, 2022

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If we're going to include this in the docs, we should probably also include that ReadOnlySpan<char> is frequently used to represent strings or slices of strings and are not guaranteed to be null-terminated.

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@jkotas jkotas Mar 3, 2022

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What is the target audience for this document? The description says "Learn about strings in C# programming." that feels like L100. It does not sound right to go into details about strings interop in the first paragraph for L100 audience.

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@Sergio0694 Sergio0694 Mar 3, 2022

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If that's the case, should we remove that mention of the null-terminator at the end of the string entirely? As in, people getting started with C# likely wouldn't know or care about what embedded null characters even are anyway, right? 🤔

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@BillWagner BillWagner Mar 3, 2022

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I think that's the better change. (Historical note: This text has been around for a long time. I'm betting it exists because a large segment of the audience for the early docs were C++ developers. This note would have been important then.)

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@jkotas jkotas Oct 16, 2024

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#43097


## string vs. System.String

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