public Expression Compile(ParameterExpression paramex)
{
Expression memberex = null;
Expression constex = Expression.Constant(RightOperand, RightOperand.GetType());
{
Match match = regex_index.Match(LeftOperand);
if (match.Success)
{
do
{
if (memberex == null)
{
memberex = Expression.PropertyOrField(paramex, match.Groups["name"].Value);
}
else
{
memberex = Expression.PropertyOrField(memberex, match.Groups["name"].Value);
}
int index;
if (int.TryParse(match.Groups["index"].Value, out index))
{
memberex = Expression.Property(memberex, "Item", Expression.Constant(index, typeof(int)));
}
} while ((match = match.NextMatch()).Success);
}
else
{
memberex = Expression.PropertyOrField(paramex, LeftOperand);
}
}
Expression condex;
switch (Operator)
{
case ExpressionOperator.Equal:
condex = Expression.Equal(memberex, constex);
break;
case ExpressionOperator.NotEqual:
condex = Expression.NotEqual(memberex, constex);
break;
case ExpressionOperator.LessThan:
condex = Expression.LessThan(memberex, constex);
break;
case ExpressionOperator.LessEqual:
condex = Expression.LessThanOrEqual(memberex, constex);
break;
case ExpressionOperator.GreaterThan:
condex = Expression.GreaterThan(memberex, constex);
break;
case ExpressionOperator.GreaterEqual:
condex = Expression.GreaterThanOrEqual(memberex, constex);
break;
case ExpressionOperator.Contains:
condex = Expression.Call(memberex, typeof(string).GetMethod("Contains", new Type[] { typeof(string) }), constex);
break;
case ExpressionOperator.NotContains:
condex = Expression.Not(Expression.Call(memberex, typeof(string).GetMethod("Contains", new Type[] { typeof(string) }), constex));
break;
case ExpressionOperator.BeginWith:
condex = Expression.Equal(Expression.Call(memberex, typeof(string).GetMethod("IndexOf", new Type[] { typeof(string) }), constex), Expression.Constant(0, typeof(int)));
break;
case ExpressionOperator.NotBeginWith:
condex = Expression.NotEqual(Expression.Call(memberex, typeof(string).GetMethod("IndexOf", new Type[] { typeof(string) }), constex), Expression.Constant(0, typeof(int)));
break;
case ExpressionOperator.EndWith: // returns memberex.LastIndexOf( constex ) == ( memberex.Length - constex.Length )
condex = Expression.Equal(
Expression.Call(memberex, typeof(string).GetMethod("LastIndexOf", new Type[] { typeof(string) }), constex),
Expression.Subtract(Expression.PropertyOrField(memberex, "Length"), Expression.PropertyOrField(constex, "Length")));
break;
case ExpressionOperator.NotEndWith: // returns memberex.LastIndexOf( constex ) != ( memberex.Length - constex.Length )
condex = Expression.NotEqual(
Expression.Call(memberex, typeof(string).GetMethod("LastIndexOf", new Type[] { typeof(string) }), constex),
Expression.Subtract(Expression.PropertyOrField(memberex, "Length"), Expression.PropertyOrField(constex, "Length")));
break;
case ExpressionOperator.ArrayContains: // returns Enumerable.Contains<>( memberex )
condex = Expression.Call(typeof(Enumerable), "Contains", new Type[] { memberex.Type.GetElementType() ?? memberex.Type.GetGenericArguments().First() }, memberex, constex);
break;
case ExpressionOperator.ArrayNotContains: // returns !Enumerable.Contains<>( memberex )
condex = Expression.Not(Expression.Call(typeof(Enumerable), "Contains", new Type[] { memberex.Type.GetElementType() ?? memberex.Type.GetGenericArguments().First() }, memberex, constex));
break;
default:
throw new NotImplementedException();
}
return(condex);
}
