public static async Task <PresentResult> FetchRecords(ZClientChannel channel,
long count)
{
var ok = channel.Enter();
try
{
if (ok == false)
{
return new PresentResult
{
Value = -1,
ErrorInfo = "通道已被占用",
ErrorCode = "channelInUse"
}
}
;
return(await _fetchRecords(channel, count).ConfigureAwait(false));
}
finally
{
channel.Exit();
}
}
static async Task <PresentResult> _fetchRecords(ZClientChannel channel,
long count)
{
if (channel._resultCount - channel._fetched > 0)
{
return(await channel.ZClient.Present(
"default",
channel._fetched,
Math.Min((int)channel._resultCount - channel._fetched, (int)count),
10,
"F",
channel.TargetInfo.PreferredRecordSyntax).ConfigureAwait(false));
}
return(new PresentResult {
Value = -1, ErrorInfo = "已经获取完成"
});
}
// 从 XML 文件中装载服务器配置信息
public NormalResult LoadServer(string xmlFileName,
Marc8Encoding marc8Encoding)
{
this.Clear();
this.XmlFileName = xmlFileName;
XmlDocument dom = new XmlDocument();
try
{
dom.Load(xmlFileName);
}
catch (Exception ex)
{
return(new NormalResult {
Value = -1, ErrorInfo = ex.Message
});
}
XmlNodeList servers = dom.DocumentElement.SelectNodes("server");
foreach (XmlElement server in servers)
{
var result = ZServerUtil.GetTarget(server,
marc8Encoding,
out TargetInfo targetInfo);
if (result.Value == -1)
{
return(result);
}
ZClientChannel channel = new ZClientChannel
{
ServerName = server.GetAttribute("name"),
ZClient = new ZClient(),
TargetInfo = targetInfo,
Enabled = ZServerListDialog.IsEnabled(server.GetAttribute("enabled"), true)
};
_channels.Add(channel);
}
return(new NormalResult());
}
// 针对一个特定 Z30.50 服务器发起检索
async Task <NormalResult> SearchOne(
ZClientChannel channel,
UseCollection useList,
IsbnSplitter isbnSplitter,
string strQueryWord,
int nMax,
string strFromStyle,
string strMatchStyle,
delegate_searchCompleted searchCompleted,
delegate_presentCompleted presentCompleted)
{
var ok = channel.Enter();
try
{
if (ok == false)
{
return(new NormalResult
{
Value = -1,
ErrorInfo = "通道已被占用",
ErrorCode = "channelInUse"
});
}
var _targetInfo = channel.TargetInfo;
IsbnConvertInfo isbnconvertinfo = new IsbnConvertInfo
{
IsbnSplitter = isbnSplitter,
ConvertStyle =
(_targetInfo.IsbnAddHyphen == true ? "addhyphen," : "")
+ (_targetInfo.IsbnRemoveHyphen == true ? "removehyphen," : "")
+ (_targetInfo.IsbnForce10 == true ? "force10," : "")
+ (_targetInfo.IsbnForce13 == true ? "force13," : "")
+ (_targetInfo.IsbnWild == true ? "wild," : "")
// TODO:
+ (_targetInfo.IssnForce8 == true ? "issnforce8," : "")
};
string strQueryString = "";
{
// 创建只包含一个检索词的简单 XML 检索式
// 注：这种 XML 检索式不是 Z39.50 函数库必需的。只是用它来方便构造 API 检索式的过程
string strQueryXml = BuildQueryXml(strQueryWord, strFromStyle);
// 将 XML 检索式变化为 API 检索式
var result = ZClient.ConvertQueryString(
useList,
strQueryXml,
isbnconvertinfo,
out strQueryString);
if (result.Value == -1)
{
searchCompleted?.Invoke(channel, new SearchResult(result));
var final_result = new NormalResult {
Value = result.Value, ErrorInfo = result.ErrorInfo
};
if (result.ErrorCode == "notFound")
{
final_result.ErrorCode = "useNotFound";
}
return(final_result);
}
}
REDO_SEARCH:
{
// return Value:
// -1 出错
// 0 成功
// 1 调用前已经是初始化过的状态，本次没有进行初始化
// InitialResult result = _zclient.TryInitialize(_targetInfo).GetAwaiter().GetResult();
// InitialResult result = _zclient.TryInitialize(_targetInfo).Result;
InitialResult result = await channel.ZClient.TryInitialize(_targetInfo);
if (result.Value == -1)
{
searchCompleted?.Invoke(channel, new SearchResult(result));
// TODO: 是否继续向后检索其他 Z39.50 服务器?
return(new NormalResult {
Value = -1, ErrorInfo = "Initialize error: " + result.ErrorInfo
});
}
}
// result.Value:
// -1 error
// 0 fail
// 1 succeed
// result.ResultCount:
// 命中结果集内记录条数 (当 result.Value 为 1 时)
SearchResult search_result = await channel.ZClient.Search(
strQueryString,
_targetInfo.DefaultQueryTermEncoding,
_targetInfo.DbNames,
_targetInfo.PreferredRecordSyntax,
"default");
if (search_result.Value == -1 || search_result.Value == 0)
{
if (search_result.ErrorCode == "ConnectionAborted")
{
// 自动重试检索
goto REDO_SEARCH;
}
}
searchCompleted?.Invoke(channel, search_result);
channel._resultCount = search_result.ResultCount;
if (search_result.Value == -1 ||
search_result.Value == 0 ||
search_result.ResultCount == 0)
{
return(new NormalResult()); // continue
}
var present_result = await _fetchRecords(channel, PresentBatchSize /*10*/);
presentCompleted?.Invoke(channel, present_result);
if (present_result.Value != -1)
{
channel._fetched += present_result.Records.Count;
}
return(new NormalResult());
}
finally
{
channel.Exit();
}
}