主题：[求助]这段代码是什么意思

Dim UserName As String = e.Form.Controls("UserName").Value
Dim cmd As New SQLCommand
Dim dt As DataTable
Dim dr As DataRow

cmd.CommandText = "Select * From {人事档案} Where [姓名] = '" & UserName & "' and [系统开启] = true"
dt = cmd.ExecuteReader

红色代码是什么意思？