class LibXML::XML::Dtd
The XML::Dtd
class is used to prepare DTD's for validation of xml documents.
DTDs can be created from a string or a pair of public and system identifiers. Once a Dtd
object is instantiated, an XML
document can be validated by the XML::Document#validate
method providing the XML::Dtd
object as parameeter. The method will raise an exception if the document is not valid.
Basic usage:
# parse DTD dtd = XML::Dtd.new(<<EOF) <!ELEMENT root (item*) > <!ELEMENT item (#PCDATA) > EOF # parse xml document to be validated instance = XML::Document.file('instance.xml') # validate instance.validate(dtd)
Public Class Methods
XML::Dtd.new("DTD string") → dtd
click to toggle source
XML::Dtd.new("public", "system") → dtd
XML::Dtd.new("name", "public", "system", document) → external subset dtd
XML::Dtd.new("name", "public", "system", document, false) → internal subset dtd
XML::Dtd.new("name", "public", "system", document, true) → internal subset dtd
Create a new Dtd
from the specified public and system identifiers.
static VALUE rxml_dtd_initialize(int argc, VALUE *argv, VALUE self) { VALUE external, system, dtd_string; xmlParserInputBufferPtr buffer; xmlCharEncoding enc = XML_CHAR_ENCODING_NONE; xmlChar *new_string; xmlDtdPtr xdtd; // 1 argument -- string --> parsujeme jako dtd // 2 arguments -- public, system --> bude se hledat // 3 arguments -- public, system, name --> creates an external subset (any parameter may be nil) // 4 arguments -- public, system, name, doc --> creates an external subset (any parameter may be nil) // 5 arguments -- public, system, name, doc, true --> creates an internal subset (all but last parameter may be nil) switch (argc) { case 3: case 4: case 5: { VALUE name, doc, internal; const xmlChar *xname = NULL, *xpublic = NULL, *xsystem = NULL; xmlDocPtr xdoc = NULL; rb_scan_args(argc, argv, "32", &external, &system, &name, &doc, &internal); if (external != Qnil) { Check_Type(external, T_STRING); xpublic = (const xmlChar*) StringValuePtr(external); } if (system != Qnil) { Check_Type(system, T_STRING); xsystem = (const xmlChar*) StringValuePtr(system); } if (name != Qnil) { Check_Type(name, T_STRING); xname = (const xmlChar*) StringValuePtr(name); } if (doc != Qnil) { if (rb_obj_is_kind_of(doc, cXMLDocument) == Qfalse) rb_raise(rb_eTypeError, "Must pass an XML::Document object"); Data_Get_Struct(doc, xmlDoc, xdoc); } if (internal == Qnil || internal == Qfalse) xdtd = xmlNewDtd(xdoc, xname, xpublic, xsystem); else xdtd = xmlCreateIntSubset(xdoc, xname, xpublic, xsystem); if (xdtd == NULL) rxml_raise(&xmlLastError); /* Document will free this dtd now. */ RDATA(self)->dfree = NULL; DATA_PTR(self) = xdtd; xmlSetTreeDoc((xmlNodePtr) xdtd, xdoc); } break; case 2: rb_scan_args(argc, argv, "20", &external, &system); Check_Type(external, T_STRING); Check_Type(system, T_STRING); xdtd = xmlParseDTD((xmlChar*) StringValuePtr(external), (xmlChar*) StringValuePtr(system)); if (xdtd == NULL) rxml_raise(&xmlLastError); DATA_PTR(self) = xdtd; xmlSetTreeDoc((xmlNodePtr) xdtd, NULL); break; case 1: rb_scan_args(argc, argv, "10", &dtd_string); Check_Type(dtd_string, T_STRING); /* Note that buffer is freed by xmlParserInputBufferPush*/ buffer = xmlAllocParserInputBuffer(enc); new_string = xmlStrdup((xmlChar*) StringValuePtr(dtd_string)); xmlParserInputBufferPush(buffer, xmlStrlen(new_string), (const char*) new_string); xdtd = xmlIOParseDTD(NULL, buffer, enc); if (xdtd == NULL) rxml_raise(&xmlLastError); xmlFree(new_string); DATA_PTR(self) = xdtd; break; default: rb_raise(rb_eArgError, "wrong number of arguments"); } return self; }
Public Instance Methods
external_id → "string"
click to toggle source
Obtain this dtd's external identifer (for a PUBLIC DTD).
static VALUE rxml_dtd_external_id_get(VALUE self) { xmlDtdPtr xdtd; Data_Get_Struct(self, xmlDtd, xdtd); if (xdtd->ExternalID == NULL) return (Qnil); else return (rxml_new_cstr((const char*) xdtd->ExternalID, NULL)); }
name → "string"
click to toggle source
Obtain this dtd's name.
static VALUE rxml_dtd_name_get(VALUE self) { xmlDtdPtr xdtd; Data_Get_Struct(self, xmlDtd, xdtd); if (xdtd->name == NULL) return (Qnil); else return (rxml_new_cstr((const char*) xdtd->name, NULL)); }
type → num
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Obtain this node's type identifier.
static VALUE rxml_dtd_type(VALUE self) { xmlDtdPtr xdtd; Data_Get_Struct(self, xmlDtd, xdtd); return (INT2NUM(xdtd->type)); }
uri → "string"
click to toggle source
Obtain this dtd's URI (for a SYSTEM or PUBLIC DTD).
static VALUE rxml_dtd_uri_get(VALUE self) { xmlDtdPtr xdtd; Data_Get_Struct(self, xmlDtd, xdtd); if (xdtd->SystemID == NULL) return (Qnil); else return (rxml_new_cstr((const char*) xdtd->SystemID, NULL)); }
Also aliased as: system_id