Hi,
But you didn't mention is it formula field or parameter field, but i give both snippets
Formula field
string strFormula ="";
strFormula = "{tblTable.fldField}='" + txtParam.text + "'";
report.DataDefinition.RecordSelectionFormula = strFormula;
Parameter field
string strParameter ="";
strParameter = txtCompanyName.Text;
report.SetParameterValue("Company", strParameter);
please let me know if you solved your issue.
Regards,
thatraja