将字符串传递给 DocumentHelper.GetDocuments().Where() 时出现异常

Question

我正在尝试获取这样的节点：

DocumentHelper.GetDocuments()
.Where("NodeParentID == 25 && NodeLevel == 2")

但出现异常：

Incorrect syntax near '='. at System.Data.SqlClient.SqlConnection.OnError(SqlException exception, Boolean breakConnection, Action1 wrapCloseInAction) at System.Data.SqlClient.TdsParser.ThrowExceptionAndWarning(TdsParserStateObject stateObj, Boolean callerHasConnectionLock, Boolean asyncClose) at System.Data.SqlClient.TdsParser.TryRun(RunBehavior runBehavior, SqlCommand cmdHandler, SqlDataReader dataStream, BulkCopySimpleResultSet bulkCopyHandler, TdsParserStateObject stateObj, Boolean& dataReady) at System.Data.SqlClient.SqlDataReader.TryConsumeMetaData() at System.Data.SqlClient.SqlDataReader.get_MetaData() at System.Data.SqlClient.SqlCommand.FinishExecuteReader(SqlDataReader ds, RunBehavior runBehavior, String resetOptionsString, Boolean isInternal, Boolean forDescribeParameterEncryption, Boolean shouldCacheForAlwaysEncrypted) at System.Data.SqlClient.SqlCommand.RunExecuteReaderTds(CommandBehavior cmdBehavior, RunBehavior runBehavior, Boolean returnStream, Boolean async, Int32 timeout, Task& task, Boolean asyncWrite, Boolean inRetry, SqlDataReader ds, Boolean describeParameterEncryptionRequest) at System.Data.SqlClient.SqlCommand.RunExecuteReader(CommandBehavior cmdBehavior, RunBehavior runBehavior, Boolean returnStream, String method, TaskCompletionSource1 completion, Int32 timeout, Task& task, Boolean& usedCache, Boolean asyncWrite, Boolean inRetry) at System.Data.SqlClient.SqlCommand.RunExecuteReader(CommandBehavior cmdBehavior, RunBehavior runBehavior, Boolean returnStream, String method) at System.Data.SqlClient.SqlCommand.ExecuteReader(CommandBehavior behavior, String method) at System.Data.Common.DbDataAdapter.FillInternal(DataSet dataset, DataTable[] datatables, Int32 startRecord, Int32 maxRecords, String srcTable, IDbCommand command, CommandBehavior behavior) at System.Data.Common.DbDataAdapter.Fill(DataSet dataSet, Int32 startRecord, Int32 maxRecords, String srcTable, IDbCommand command, CommandBehavior behavior) at System.Data.Common.DbDataAdapter.Fill(DataSet dataSet) at CMS.DataEngine.AbstractDataConnection.ExecuteQuery(String queryText, QueryDataParameters queryParams, QueryTypeEnum queryType, Boolean requiresTransaction) --- End of inner exception stack trace ---
at CMS.DataEngine.AbstractDataConnection.HandleError(String queryText, Exception ex) at CMS.DataEngine.AbstractDataConnection.ExecuteQuery(String queryText, QueryDataParameters queryParams, QueryTypeEnum queryType, Boolean requiresTransaction) at CMS.DataEngine.GeneralConnection.RunQuery(QueryParameters query) at CMS.DataEngine.GeneralConnection.RunQueryWithRetry(QueryParameters query, Int32 retryCount) at CMS.DataEngine.GeneralConnection.ExecuteQuery(QueryParameters query, Int32& totalRecords) at CMS.DataEngine.DataQueryBase1.GetDataFromDBInternal() at CMS.DataEngine.DataQueryBase1.GetDataFromDB() at CMS.DataEngine.DataQueryBase1.GetData() at CMS.DataEngine.DataQueryBase1.get_Result() at CMS.DataEngine.DataQueryBase1.GetResults(IDataQuery query, Int32& totalRecords) at CMS.DataEngine.DataQueryBase1.GetDataFromDB()
at CMS.DocumentEngine.DocumentQueryProperties.GetDataInternal(IDocumentQuery query, Func1 baseGetDataMethod, Action1 setTotalRecords) at CMS.DataEngine.DataQueryBase1.GetData() at CMS.DataEngine.DataQueryBase1.get_Result() at CMS.DataEngine.MultiObjectQueryBase3.EnsureTypedResult() at CMS.DataEngine.MultiObjectQueryBase3.GetEnumerator() at System.Collections.Generic.List1..ctor(IEnumerable1 collection)
at System.Linq.Enumerable.ToList[TSource](IEnumerable`1 source)

我做错了什么？

Answer 1

== 是一种 C# 语法，SQL 只使用一个 =.

你应该像这样做你的 where 条件：

 .Where("NodeParentID", QueryOperator.Equals, 25)        
    .Where("NodeLevel ", QueryOperator.Equals, 7);

Answer 2

您的 SQL 语法在您的 "WHERE" 子句中不正确。您正在尝试在需要使用 T-SQL

的地方使用 C# 语法

不正确：

DocumentHelper.GetDocuments().Where("NodeParentID == 25 && NodeLevel == 2");

正确：

DocumentHelper.GetDocuments().Where("NodeParentID = 25 AND NodeLevel = 2");