System. NullReferenceException generated when SubSonic3.0 plug-in uses SqlQuery or Select query

　　

You have not set the object reference to the instance of the object.

Note:An unhandled exception occurred during the execution of the current Web request. Check the stack trace information for details about the error and the source of the error in the code.

Exception details:System. NullReferenceException: object reference is not set to the instance of the object.

Source error:

Row 168: foreach (Constraint constrain c) Row 169: {row 171: constrain. ColumnName = column. Name; row 172: constrain. ConstructionFragment = column. Name;

Source file:E: \ Asp.net \ ******* \ SubSonic. Core \ Query \ SqlQuery. csRow:170

Stack trace:

[NullReferenceException: object reference is not set to the instance of the object.] SubSonic. query. sqlQuery. where (Expression '1 expression) in E: \ Asp.net \ SubSonic. core \ Query \ SqlQuery. cs: 170 SubSonicTest. test. page_Load (Object sender, EventArgs e) in E: \ Asp.net \ SubSonicTest \ Test. aspx. cs: 19 System. web. util. calliEventHandlerDelegateProxy. callback (Object sender, EventArgs e) + 51 System. web. UI. control. onLoad (EventArgs e) + 92 System. web. UI. control. loadRecursive () + 54 System. web. UI. page. processRequestMain (Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) + 772

　　

After Tracing Through Debug, it is found that in the SqlQuery class condition adding function, after obtaining the generic class through reflection, find the condition column name and assign a value to the condition column, exception caused by this column not found

Modify the table object corresponding to the generic type to add a judgment. If it is null, modify the table object as follows:

　　

　　

SqlQuery Where <T> (Expression <Func <T,> expression) T: IList <Constraint> c = iTable = _ provider. findTable (iTable ===_ provider. findOrCreateTable <T> (Constraint constrain IColumn column ======View Code

 

　　

After the above Code is added, you can use the SubSonic3.0 plug-in source code again.

 

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