This article covers features introduced in SpiderMonkey 38

Return a specified character from a string.


JS_GetStringCharAt(JSContext *cx, JSString *str, size_t index, char16_t *res);

JS_GetFlatStringCharAt(JSFlatString *str, size_t index);
Name Type Description
cx JSContext * The context in which to create the new string. Requires request. In a JS_THREADSAFE build, the caller must be in a request on this JSContext.
str JSString * or JSFlatString * The string to get character.
index size_t An integer between 0 and 1-less-than the length of the string.
res char16_t * (JS_GetStringCharAt only) Out parameter. On successful, receives the character code.


JS_GetStringCharAt and JS_GetFlatStringCharAt get the specified character from the string str.

On successful, JS_GetStringCharAt returns true and stores the character code into *res, otherwise returns false.

JS_GetFlatStringCharAt always succeeds, and returns the character code.

index should not be greater than or equal to the length of str.

See Also