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Dynamic LINQ Where problem

Posted By:      Posted Date: October 11, 2010    Points: 0   Category :ASP.Net
 

Guys

I am using LINQ TO ENTITIES.

I stumbled upon a problem while using Dynamic LINQ which is provided by Scott Guthrie. Basically I need a functionality where the user would be able to search by anything while on a gridview. Now the issue is that when the field to be searched is a string it works without problems, when it is an interger it is giving me a {"Operator '=' incompatible with operand types 'Int32?' and 'String'"}. Now the issue is that I would not be able to know what datatype the field is. If I convert the data to an INT it works without problems, but as I said I cannot since I would not be able to know beforehand the database data type. The place where it is giving me the error is shown in bold.

 

The second issue is that I have a CONTAINS functionality where the user would be able to type in anything and the system will create a CONTAINS linq statement to search for data. For one field it works without problems, while for another field the CONTAINS does not work and it gives me an OBJECT NOT SET TO AN INSTANCE when I try to access the list.  The code is shown underneath. I am using MVC and jqGrid.

private static string BuildWhereClause(JQGridRequest.SearchOperatorOptions SearchOperator, string FieldName)

{

 

swit


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