Hi i'm having an error from my code conversion from type 'dbnull' to type 'string' is not valid

please help.

code:

Private Sub DataGridView1_CellContentClick(sender As Object, e As DataGridViewCellEventArgs) Handles DataGridView1.CellContentClick

    txt_ID.Text = DataGridView1.CurrentRow.Cells(0).Value
    txt_DATE.Text = DataGridView1.CurrentRow.Cells(1).Value
    txt_FNAME.Text = DataGridView1.CurrentRow.Cells(2).Value
    txt_LNAME.Text = DataGridView1.CurrentRow.Cells(3).Value
    txt_AGE.Text = DataGridView1.CurrentRow.Cells(4).Value
    txt_SEX.Text = DataGridView1.CurrentRow.Cells(5).Value
    txt_REGNO.Text = DataGridView1.CurrentRow.Cells(6).Value
    txt_ROOMNO.Text = DataGridView1.CurrentRow.Cells(7).Value
    txt_HEIGHT.Text = DataGridView1.CurrentRow.Cells(8).Value
    txt_WEIGHT.Text = DataGridView1.CurrentRow.Cells(9).Value
    txt_CELLNO.Text = DataGridView1.CurrentRow.Cells(10).Value
    txt_ADDRESS.Text = DataGridView1.CurrentRow.Cells(11).Value
    txt_TELLNO.Text = DataGridView1.CurrentRow.Cells(12).Value
    txt_FAXNO.Text = DataGridView1.CurrentRow.Cells(13).Value
    txt_EMAIL.Text = DataGridView1.CurrentRow.Cells(14).Value
    txt_REFERMD.Text = DataGridView1.CurrentRow.Cells(15).Value
    txt_MD.Text = DataGridView1.CurrentRow.Cells(16).Value
    txt_ANES.Text = DataGridView1.CurrentRow.Cells(17).Value
    txt_PROC.Text = DataGridView1.CurrentRow.Cells(18).Value
    txt_INDICATION.Text = DataGridView1.CurrentRow.Cells(19).Value
    txt_XRAY.Text = DataGridView1.CurrentRow.Cells(20).Value
    txt_TARGET.Text = DataGridView1.CurrentRow.Cells(21).Value
    txt_PREP1.Text = DataGridView1.CurrentRow.Cells(22).Value
    txt_PREP2.Text = DataGridView1.CurrentRow.Cells(23).Value
    txt_PREP3.Text = DataGridView1.CurrentRow.Cells(24).Value
    txt_QUALITY.Text = DataGridView1.CurrentRow.Cells(25).Value
    txt_SEGMENT.Text = DataGridView1.CurrentRow.Cells(26).Value
    txt_BBP.Text = DataGridView1.CurrentRow.Cells(27).Value
    txt_PREMED.Text = DataGridView1.CurrentRow.Cells(28).Value
    txt_SCOPE.Text = DataGridView1.CurrentRow.Cells(29).Value
    txt_PROCTIME.Text = DataGridView1.CurrentRow.Cells(30).Value
    txt_FINDINGS.Text = DataGridView1.CurrentRow.Cells(31).Value
    txt_BIOPSY.Text = DataGridView1.CurrentRow.Cells(32).Value
    txt_LOC.Text = DataGridView1.CurrentRow.Cells(33).Value
    txt_CYTOLOGY.Text = DataGridView1.CurrentRow.Cells(34).Value
    txt_SIZE.Text = DataGridView1.CurrentRow.Cells(35).Value
    txt_ENDODESC.Text = DataGridView1.CurrentRow.Cells(36).Value
    txt_THERAPEUTIC.Text = DataGridView1.CurrentRow.Cells(37).Value
    txt_COMPLICATIONS.Text = DataGridView1.CurrentRow.Cells(38).Value
    txt_DIAGNOSIS.Text = DataGridView1.CurrentRow.Cells(39).Value
    txt_OUTCOME.Text = DataGridView1.CurrentRow.Cells(40).Value
    txt_LATECOMP.Text = DataGridView1.CurrentRow.Cells(41).Value
    txt_HISTOPATH.Text = DataGridView1.CurrentRow.Cells(42).Value
    txt_ENDOSPCOPIST.Text = DataGridView1.CurrentRow.Cells(43).Value

End Sub

CodePudding user response：

Add ToString in that code.

 txt_ID.Text = DataGridView1.CurrentRow.Cells(0).Value.ToString()

or put if condition to check value is null or not like below

  IF not DataGridView1.CurrentRow.Cells(0).Value is dbnull Then
    txt_ID.Text = DataGridView1.CurrentRow.Cells(0).Value
  EndIF

But this is very basic level.

Regards Aravind

CodePudding user response：

Try the CheckDBNull function. :)

 ex) txt_PREP1.Text = CheckDBNull(DataGridView1.CurrentRow.Cells(22).Value)

Public Function CheckDBNull(ByVal oData As Object) As String
      Try
         Dim sResult As String
         If TypeOf oData Is DBNull Then
            sResult = ""
         Else
            sResult = Trim(CType(oData, String))
         End If
         Return sResult

      Catch ex As Exception
         Return ""
      End Try
   End Function