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PONullreference excpetion was unhandled (Object reference not set to an instance of an object)
 

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  1. PONullreference excpetion was unhandled (Object reference not set to an instance of an object)
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    <p>I have a form with four combobxes say cbmefrom(age from ) cbmeto( age to) cbperiod(periodtype values liek this "Next 7 Days" ......) and cbgender(cbgender)..</p> <p>i have a datagrid view also(dgvreports)..</p> <p>what i am trying to do is i am populating the members details those whoose age is between 20 to 40 and whoose membership will expire in next 8 days or 24 days or like that ...</p> <p>for that i have written one class that i have specified below...</p> <pre><code> public static string ConvertGender(string Gender) { switch (Gender) { case "Male": return "M"; case "Female": return "F"; default: return ""; } } public BindingSource getmebershipexpirymembers(string gender , DateTime strtdate,DateTime enddate,DateTime min , DateTime max) { bs2.DataSource = null; var membersreports = from report in eclipse.members let dob= eclipse.members.Take(1).Select(x=&gt;report.member_Dob).Cast&lt;DateTime&gt;().FirstOrDefault() let strtdatees = eclipse.membertomships.Take(1).Select(x=&gt;x.memberToMship_EndDate).Cast&lt;DateTime&gt;().FirstOrDefault() join memtomship in eclipse.membertomships on report.member_Id equals memtomship.member_Id into joinmemtomship from memtomship in joinmemtomship.DefaultIfEmpty() join mshoption in eclipse.mshipoptions on memtomship.mshipOption_Id equals mshoption.mshipOption_Id into joinmshipoption from mshoption in joinmshipoption.DefaultIfEmpty() join membershiptypes in eclipse.mshiptypes on mshoption.mshipType_Id equals membershiptypes.mshipType_Id into joinmembershipdifftypes from membershiptypes in joinmembershipdifftypes.DefaultIfEmpty() join membershipstatustypes in eclipse.mshipstatustypes on memtomship.mshipStatusType_Id equals membershipstatustypes.mshipStatusType_Id into joinmemberstatusdifftypes from membershipstatustypes in joinmemberstatusdifftypes.DefaultIfEmpty() where (report.member_Gender.StartsWith(gender) || string.IsNullOrEmpty(gender)) &amp;&amp; dob &gt;= min &amp;&amp; dob &lt; max &amp;&amp; (strtdatees &gt; strtdate &amp;&amp; strtdatees &lt; enddate) select new { MemberID = report.member_Id, Lastname = report.member_Lastname, Firstname = report.member_Firstname, Postcode = report.member_Postcode, Reference = report.member_Reference, CardNum = report.member_CardNum, IsBiometric = report.member_IsBiometric, DOB = report.member_Dob, MShipType = membershiptypes.mshipType_Name, StatusType = membershipstatustypes.mshipStatusType_Name, EndDate = memtomship.memberToMship_EndDate }; bs2.DataSource = membersreports; return bs2; } </code></pre> <p>and i am accessing above class in the form that i have mentioned below...</p> <pre><code> public void Getgroupcorporatemembers() { int startdays = 0; int enddays = 0; if (cbMeperiodType.Text == membershipexpiry.type1) { startdays = 0; enddays = 7; } if (cbMeperiodType.Text == membershipexpiry.type2) { startdays = 8; enddays = 14; } if (cbMeperiodType.Text == membershipexpiry.type3) { startdays = 15; enddays = 30; } if (cbMeperiodType.Text == membershipexpiry.type4) { startdays = 31; enddays = 90; } DateTime today = DateTime.Now; DateTime strtdate = today.AddDays(startdays); DateTime enddate = today.AddDays(enddays); int agefrom = Convert.ToInt32(cbMeFrom.Text); int ageto = Convert.ToInt32(CbMeTo.Text); DateTime max = today.AddYears(-agefrom); DateTime min = today.AddYears(-ageto); string gender = ""; gender = Classes.reportmembers.ConvertGender(cbMEGendertype.Text); dgvReportMembers.DataSource = objreports.getmebershipexpirymembers(gender, strtdate, enddate, max, min);// here i am accessing the method in class SetDgvheaders(); } struct membershipexpiry { public const string type1 = "Next 7 Days"; public const string type2 = "8 - 14 Days"; public const string type3 = "15 - 30 Days"; public const string type4 = "31 - 90 Days"; } </code></pre> <p>but I am getting the error at this line ... <code>bs2.DataSource = membersreports;</code></p> <pre><code> Error :Nullreference excpetion was unhandled Object reference not set to an instance of an object. </code></pre>
    singulars
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. PTQuestion
    1. USJohn Saunders
    1. USEnigma State
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      1. LTLinked
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. PO
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    2. PO
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    1. This table or related slice is empty.
    1. CO@Yochai - But then the first line of the function would throw the exception.
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      1. PONullreference excpetion was unhandled (Object reference not set to an instance of an object)
      1. USOded
    2. CO@Yochai nope. something in the query is null. The query gets evaluated only when it's assigned to the datasource and hence the null reference exception occurs on that line.
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      1. PONullreference excpetion was unhandled (Object reference not set to an instance of an object)
      1. USBala R
    3. CO@Oded i am sure i am getting null reference exception at this line "bs2.DataSource = membersreports;"
      singulars
      1. PONullreference excpetion was unhandled (Object reference not set to an instance of an object)
      1. USEnigma State
 

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