protected override Expression VisitMethodCall(MethodCallExpression m)
{
switch (m.Method.Name)
{
case "Where":
this.Visit(m.Arguments[0]);
sb.Append(" WHERE ");
LambdaExpression lambda = (LambdaExpression)StripQuotes(m.Arguments[1]);
this.Visit(lambda.Body);
return(m);
case "Associators":
var arg = (ConstantExpression)m.Arguments[0];
sb.Append("ASSOCIATORS OF {");
sb.Append(WmiObject.GetClassName(arg.Value.GetType()));
sb.Append("=\"");
sb.Append(WmiObject.GetWmiQueryValue(((WmiObject)arg.Value).ID));
sb.Append("\"} WHERE ResultClass=");
sb.Append(WmiObject.GetClassName(m.Method.GetGenericArguments()[0]));
return(m);
case "Contains":
this.Visit(m.Object);
sb.Append(" LIKE \"%");
var oldSB = sb;
sb = new StringBuilder();
this.Visit(m.Arguments[0]);
var s = sb.ToString();
sb = oldSB;
sb.Append(s.Substring(1, s.Length - 2));
sb.Append("%\"");
return(m);
}
throw new NotSupportedException(string.Format("The method '{0}' is not supported", m.Method.Name));
}
public static IEnumerable <TResult> Associators <TResult>(this WmiObject source)
where TResult : WmiObject <TResult>, new()
{
var q = new WmiQuery <TResult>(source.CreationContext, Expression.Call(((MethodInfo)MethodBase.GetCurrentMethod()).MakeGenericMethod(
typeof(TResult)), Expression.Constant(source, typeof(WmiObject))));
return(q);
}
protected override Expression VisitConstant(ConstantExpression c)
{
IWmiQueryable q = c.Value as IWmiQueryable;
if (q != null)
{
// assume constant nodes w/ IQueryables are table references
if (sb.Length == 0)
{
sb.Append("SELECT ");
if (m_FetchAllFields)
{
sb.Append("*");
}
else
{
sb.Append(string.Join(",", WmiObject.GetWmiPropertyNames(q.ElementType)));
}
sb.Append(" FROM ");
}
sb.Append(WmiObject.GetClassName(q.ElementType));
}
else if (c.Value == null)
{
sb.Append("NULL");
}
else
{
switch (Type.GetTypeCode(c.Value.GetType()))
{
case TypeCode.Boolean:
sb.Append(((bool)c.Value) ? 1 : 0);
break;
case TypeCode.String:
sb.AppendFormat("\"{0}\"", WmiObject.GetWmiQueryValue(c.Value));
break;
case TypeCode.Object:
throw new NotSupportedException(string.Format("The constant for '{0}' is not supported", c.Value));
default:
sb.Append(c.Value);
break;
}
}
return(c);
}
public IEnumerator <TResult> Execute <TResult>(IWmiQueryable query)
where TResult : WmiObject <TResult>, new()
{
if (m_QueryBuilder == null)
{
m_QueryBuilder = new WmiQueryBuilder(this);
}
var querystring = m_QueryBuilder.Translate(query, m_FetchAllFields);
var objQuery = new ObjectQuery(querystring);
var wmiSearcher = new ManagementObjectSearcher(m_Scope, objQuery);
Debug.WriteLine(querystring);
foreach (ManagementObject o in wmiSearcher.Get().Cast <ManagementObject>())
{
yield return(WmiObject.CreateObject <TResult>(this, o));
}
wmiSearcher.Dispose();
}
protected override Expression VisitMember(MemberExpression m)
{
if (m.Expression != null && m.Expression.NodeType == ExpressionType.Parameter)
{
if (m.Member.Name == "ID")
{
sb.Append(WmiObject.GetKeyPropertyName(m.Expression.Type));
}
else
{
var a = m.Member.GetCustomAttribute <WmiPropertyAttribute>();
if (a == null)
{
throw new MemberAccessException(string.Format("'{0}' is not a WMI property of class '{1}'", m.Member.Name, m.Type.Name));
}
sb.Append(a.Property ?? m.Member.Name);
}
return(m);
}
throw new NotSupportedException(string.Format("The member '{0}' is not supported", m.Member.Name));
}
