try
{
int MemberId = 0;
if (textBox1.Text != "")
{
Mydata.Clear();
MemberId = Convert.ToInt32(textBox1.Text.Trim());
if (member.Exists(MemberId))
{
da = new MySqlDataAdapter("select a.MemberId as MemberId,MemberName,type, if(type=0, CAST(Score as CHAR(20)) ,if(Score=0,'不合格','合格') ) as Score from member as a left join memscore as b on a.memberid = b.memberid where a.memberid=" + MemberId + "", conn);
da.Fill(Mydata, "MyReportDataTable");