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System.dbnull.value not working ..

Posted By:      Posted Date: September 07, 2010    Points: 0   Category :ASP.Net
 
For Each itm As GridViewRow In grid.Rows keyVal = grid.DataKeys(itm.RowIndex).Value If CType(itm.FindControl("chkSelect"), CheckBox).Checked Then Dim Advlnk As New AdvanceLink(keyVal) If CType(itm.FindControl("lblLastRMTest"), Label).Equals(System.DBNull.Value) Then ' If Advlnk.RMTest.Equals(System.DBNull.Value) Then Response.Write("this is null") I have tried different ways. ... How do I test my integer column for DBNull? I tried    If IsDBNull(Advlnk.RMTest) Then Response.Write( "this is null")     and this doesn't work either.


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In the code behind

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Xinguo

 

Error attached below:

Unable to cast object of type 'System.DBNull' to type 'System.String'.

Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.

Exception Details: System.InvalidCastException: Unable to cast object of type 'System.DBNull' to type 'System.String'.

Source Error:

Line 1178:            get {
Line 1179:                try {
Line 1180:                    return ((string)(this[this.tablemember.CurrentCityStateColumn]));
Line 1181:                

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hello i have the following problem

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Public Sub CustomValidator1_ServerValidate(ByVal source As Object, ByVal args As System.Web.UI.WebControls.ServerValidateEventArgs) Handles CustomValidator1.ServerValidate
       

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