Visual Studio Error Message Summary

1. Error message: JavaScript runtime error: '$' is undefined

Solution: index.cshtml 这个页面
insert into

2. Error Message: when debug/run a solution, it pop up the 'unable to launch the IIS Express Web server. Output from IIS Express Port '11159' is in use '.

Solution: delete the file in //c$/document/IISExpress. Try to debug/run the solution again.

3. Error message: when try to debug/run a solution for the first time, it pop up the error message 'could not find a part of the path 'E:\website\PRC Tools WebProject**.WebSite\bin\roslyn\csc.exe'. '

Solution: rebuild the solution, then try to debug/run the solution again.
reference: http://www.ridilabs.net/post/2018/11/02/Could-not-find-a-part-of-the-path-rosyln-cscexe.aspx#.XVoBPeQUlMs

4. Inconsistent accessibility: parameter type 'MailTask' is less accessible than method ''

   Solution: project Model class prefix add a keyword Public

5. Sequence contains no elements
   advise:
   When you get the LINQ error "Sequence contains no elements", this is usually because you are using the First() or Single() command rather than FirstOrDefault() and SingleOrDefault().
   Solution:
   Change Single() to SingleOrDefault()

6. Index was out of range. Must be non-negative and less than the size of the collection.
   Parameter name: index

7. Error: Cannot bind to the new display member. Parameter name: newDisplayMember.

original: cbxpmn. valueMember = dt.rows[0]["Menu_Name"].tostring();
cbxpmn.DisplayMember = dt.Rows[0]["Menu_Name"].tostring();

Update: cbxpmn.ValueMember = "Menu_Name";
cbxpmn.DisplayMember = "Menu_Name";