User Guide

The C-level API 359
Returns
A Boolean value: JS_TRUE indicates success; JS_FALSE indicates failure.
JSBool JS_StringToValue()
Description
This function stores a string return value in a jsval structure. It allocates a new JavaScript string
object.
Arguments
JSContext *cx
, char *bytes, size_t sz, jsval *vp
• The cx argument is the opaque JSContext pointer that passes to the JavaScript function.
• The bytes argument is the string to be stored in the jsval structure. The string data is copied,
so the caller should free the string when it is not needed. If the string size is not specified (see
the
sz argument), the string must be null-terminated.
• The sz argument is the size of the string, in bytes. If sz is 0, the length of the null-terminated
string is computed automatically.
• The vp argument is a pointer to the jsval structure into which the contents of the string
should be copied.
Returns
A Boolean value: JS_TRUE indicates success; JS_FALSE indicates failure.
JSBool JS_DoubleToValue()
Description
This function stores a floating-point number return value in a jsval structure.
Arguments
JSContext *cx
, double dv, jsval *vp
• The cx argument is the opaque JSContext pointer that passes to the JavaScript function.
• The dv argument is an 8-byte floating-point number.
• The vp argument is a pointer to the jsval structure into which the contents of the double
should be copied.
Returns
A Boolean value: JS_TRUE indicates success; JS_FALSE indicates failure.