public static Expression ConvertToBool(this Expression E)
{
if (E.Type == typeof(bool))
{
return(E);
}
else if (NumericType.Contains(E.Type))
{
return(Expression.GreaterThan(E, Expression.Constant(0, typeof(int))));
}
else if (E.Type == typeof(string))
{
return(Expression.NotEqual(Expression.Constant("", typeof(string)), E));
}
else
{
return(Expression.NotEqual(E, Expression.Constant(null)));
}
}
public static Expression ConvertToNumber(this Expression E, Type Favorite = null)
{
if (E.GetType() == typeof(ConstantExpression))
{
return(((ConstantExpression)E).ConvertTo(Favorite ?? typeof(double)));
}
if (NumericType.Contains(E.Type))
{
if (E.Type == Favorite)
{
return(E);
}
else if (Favorite != null)
{
return(Expression.Convert(E, Favorite));
}
}
if (E.GetType() == typeof(VarAutExpression))
{
return(((VarAutExpression)E).Getter(Favorite ?? typeof(double)));
}
if (NumericType.Contains(E.Type))
{
return((Favorite != null && E.Type != Favorite) ? Expression.Convert(E, Favorite) : E);
}
else if (E.Type == typeof(string))
{
return(Expression.Call(Numeric_Parse(Favorite ?? typeof(double)), E, InvariantCultureFieldAccess));
}
else if (E.Type == typeof(bool))
{
return(Expression.IfThenElse(E, Expression.Constant(1, Favorite ?? typeof(int)), Expression.Constant(0, Favorite ?? typeof(int))));
}
else
{
return(Expression.Convert(Expression.Call(Convert_ChangeType, Expression.Convert(E, typeof(object)), Expression.Constant(Favorite, typeof(Type))), Favorite));
}
}
public static Expression ConvertTo(this Expression E, Type T)
{
if (E.GetType() == typeof(ConstantExpression))
{
return(((ConstantExpression)E).ConvertTo(T));
}
if (E.GetType() == typeof(VarAutExpression))
{
return(((VarAutExpression)E).Getter(T));
}
if (E.Type == T)
{
return(E);
}
else if (T == typeof(string))
{
return(E.ConvertToString());
}
else if (NumericType.Contains(T))
{
return(E.ConvertToNumber(T));
}
else if (T == typeof(bool))
{
return(E.ConvertToBool());
}
else if (T == typeof(object))
{
return(Expression.Convert(E, T));
}
else
{
return(Expression.Convert(Expression.Call(Convert_ChangeType, Expression.Convert(E, typeof(object)), Expression.Constant(T, typeof(Type))), T));
}
}
public static Expression ConvertTo(this ConstantExpression E, Type T)
{
if (E.Type == T)
{
return(E);
}
if (T == typeof(string)) //Convert to string ?
{
return(Expression.Constant(Convert.ToString(E.Value, CultureInfo.InvariantCulture), T));
}
/*else if (NumericType.Contains(T)) //Convert to number ?
* return Expression.Constant(Convert.ToDouble(E.Value, CultureInfo.InvariantCulture), T);*/
if (T == typeof(bool))
{
return(Expression.Constant(E.Type == typeof(string) ? (string)E.Value != "" : NumericType.Contains(E.Value) ? (dynamic)E.Value > 0 : E.Value != null, T));
}
if (T == typeof(object))
{
return(Expression.Convert(E, T));
}
else
{
try //It's an IConvertible ?
{
return(Expression.Constant(Convert.ChangeType(E.Value, T), T));
}
catch //It's not, return default
{
return(Expression.Constant(T.DefaultValue(), T));
}
}
}
