[#bsl-basic_string-0e-operator_plus_eq-07] = xref:bsl.adoc[bsl]::xref:bsl/basic_string-0e.adoc[basic_string<wchar_t>]::operator+= :relfileprefix: ../../ :mrdocs: Append the specified null‐terminated `rhs` string (of length `CHAR_TRAITS::length(rhs)`) to this string, and return a reference providing modifiable access to this string. == Synopsis Declared in `<bslstl_string.h>` [source,cpp,subs="verbatim,replacements,macros,-callouts"] ---- xref:bsl/basic_string-0faf.adoc[basic_string<wchar_t>]& operator+=(wchar_t const* rhs); ---- [.small]#Created with https://www.mrdocs.com[MrDocs]#