[#BloombergLP-bdlde-Utf8Util-numCharactersIfValid-0a]
= xref:BloombergLP.adoc[BloombergLP]::xref:BloombergLP/bdlde.adoc[bdlde]::xref:BloombergLP/bdlde/Utf8Util.adoc[Utf8Util]::numCharactersIfValid
:relfileprefix: ../../../
:mrdocs:

Return the Unicode code‐point count if `string` is valid UTF‐8.

== Synopsis

Declared in `<bdlde_utf8util.h>`

[source,cpp,subs="verbatim,replacements,macros,-callouts"]
----
static
xref:BloombergLP/bdlde/Utf8Util/IntPtr.adoc[Utf8Util::IntPtr]
numCharactersIfValid(
    char const** invalidString,
    char const* string,
    xref:BloombergLP/bdlde/Utf8Util/size_type.adoc[size_type] length);
----

== Description

Otherwise, return a negative value and load into `invalidString` the address of the byte after the last valid Unicode code point traversed. `string` need not be null‐terminated and may contain embedded null bytes, and `string` may be null if `0 == length` (see {Empty Input Strings}). Note that `string` may contain less than `length` Unicode code points.

== Return Value

code‐point count on success, or a negative value on invalid UTF‐8

== Parameters

[cols="1,4"]
|===
| Name| Description
| *invalidString*
| if non‐null, set to the first invalid byte on error
| *string*
| UTF‐8 byte sequence to examine
| *length*
| length of `string` in bytes
|===


[.small]#Created with https://www.mrdocs.com[MrDocs]#