如何使查询返回的类型为string啊

[pgy8288]

这个查询出来的结果不对，尤其是username项，他的值类型是string ,但是好象下面的查询返回的结果是int，我该如何更改下面的查询啊？麻烦各位大侠指点一下啊
Sub btnClick_Search(S As Object,E As EventArgs)
Dim username As String
Dim userid As String
username=txtSuser.Text
userid=txtSID.Text
conMyData=New SqlConnection("Server=Localhost;UID=sa;PWD=1;DataBase=Exam")
If txtSID.Text = "" and txtSuser.Text = "" Then
cmdSelect=New SqlCommand("Select userlist.*,dept.* from userlist,dept where dept.id=userlist.did order by userlist.id",conMyData)
End If
If txtSID.Text <> "" and txtSuser.Text = "" Then
cmdSelect=New SqlCommand("Select userlist.*,dept.* from userlist,dept where userlist.id=@id and dept.id=userlist.did order by userlist.id",conMyData)
End If
If txtSuser.Text <> "" and txtSID.Text = "" Then
cmdSelect=New SqlCommand("Select userlist.*,dept.* from userlist,dept where username=@name and dept.id=userlist.did order by userlist.id",conMyData)
End If
If txtSuser.Text <> "" and txtSID.Text <> "" Then
cmdSelect=New SqlCommand("Select userlist.*,dept.* from userlist,dept where username=@name and userlist.id=@id and dept.id=userlist.did order By userlist.id",conMyData)
End If
cmdSelect.Parameters.Add("@id",userid)
cmdSelect.Parameters.Add("@name",username)

conMyData.Open()
dgrdUser.DataSource=cmdSelect.ExecuteReader()
dgrdUser.DataBind()
conMyData.Close()
End Sub

[NEODIO]

ExecuteReader()得到DataReader后
while(reader.Read())
{
username = reader.GetString(0);
}

即可

[pgy8288]

这样不行啊
会编译错误

[yzgnick]

ExecuteReader()得到DataReader后
while(reader.Read())
{
username = reader.ToString();
}

即可

[pgy8288]

这个方法我也试过了啊
他说username没有定义，如果根据上面的来写
While dtrList.Read
username=dtrList.GetString(0)或username=dtrList.ToString()
End While
还有
改了之后如何才能返回上面查询所需要的所有结果呢？

[pgy8288]

已解决