// 根据 use 的名称，获得可用于 API 的 use 值
public async Task <string> GetUseValue(SruTarget target, string use_name)
{
var lines = await ListUses(target).ConfigureAwait(false);
foreach (var line in lines)
{
if (line.Name == use_name)
{
return(line.Value);
}
if (line.Value == use_name)
{
return(line.Value);
}
}
return(null);
}
// 列出一个检索目标的所有可用检索途径
public async Task <List <NameValueLine> > ListUses(SruTarget target)
{
List <NameValueLine> results = new List <NameValueLine>();
XmlNamespaceManager nsmgr = new XmlNamespaceManager(new NameTable());
nsmgr.AddNamespace("srw", "http://www.loc.gov/zing/srw/");
nsmgr.AddNamespace("explain20", "http://explain.z3950.org/dtd/2.0/");
nsmgr.AddNamespace("explain21", "http://explain.z3950.org/dtd/2.1/");
/*
*
* <explain xmlns="http://explain.z3950.org/dtd/2.0/" xmlns:ns="http://explain.z3950.org/dtd/2.1/">
* <serverInfo>
* <ns:host>bibsys-network.alma.exlibrisgroup.com</ns:host>
* <ns:port>80</ns:port>
* <ns:database>47BIBSYS_NETWORK</ns:database>
* </serverInfo>
* <indexInfo>
* <set name="alma" identifier="marcxml"/>
* <index>
* <ns:title>Accompanying Material</ns:title>
* <map>
* <name set="alma">accompanying_material</name>
* </map>
* <configInfo>
* <supports type="relation">all</supports>
* <supports type="relation">=</supports>
* <supports type="emptyTerm"/>
* </configInfo>
* </index>
* <index>
* <ns:title>Additional physical form available note</ns:title>
* <map>
* <name set="alma">additional_physical_form_available_note</name>
* </map>
* <configInfo>
* <supports type="relation">all</supports>
* <supports type="relation">=</supports>
* <supports type="relation">==</supports>
* </configInfo>
* </index>
* */
XmlDocument dom = await GetExplainDomAsync(target.Name,
"explain",
target.GetExplainUrl()).ConfigureAwait(false);
XmlNodeList nodes = dom.DocumentElement.SelectNodes("//explain20:indexInfo/explain20:index", nsmgr);
foreach (XmlElement index in nodes)
{
string title = index.SelectSingleNode("explain21:title", nsmgr)?.InnerText;
XmlElement map = index.SelectSingleNode("explain20:map/explain20:name", nsmgr) as XmlElement;
string set = map.GetAttribute("set");
NameValueLine line = new NameValueLine(title, $"{set}.{map.InnerText}");
results.Add(line);
}
return(results);
}