private static SqlExpression VisitMethodCall(MethodCallExpression methodCallExpression)
{
if (methodCallExpression.Method.DeclaringType.Name == "String") {
return new SqlWhereClause { Left = Visit(methodCallExpression.Object), Operator = SqlOperator.Like, Right = VisitLike(Visit(methodCallExpression.Arguments[0]), methodCallExpression) };
}
if (methodCallExpression.Method.Name == "Contains") {
var arg = ((SqlWhereConstant)Visit(methodCallExpression.Arguments[0])).Value;
var column = (MemberExpression)methodCallExpression.Arguments[1];
var left = new SqlWhereColumn { Prefix = ((ParameterExpression)column.Expression).Name, Name = QueryTranslator.GetColumnName(column.Member) };
var right = new SqlWhereConstant { Value = arg };
var opera = SqlOperator.In;
return new SqlWhereClause { Left = left, Operator = opera, Right = right };
}
if (Type.GetTypeCode(methodCallExpression.Method.ReturnType) != TypeCode.Object) {
var objExpression = Visit(methodCallExpression.Object);
if (objExpression is SqlWhereConstant) {
var args = GetArgumentsValue(methodCallExpression.Arguments);
return new SqlWhereConstant { Value = methodCallExpression.Method.Invoke(((SqlWhereConstant)objExpression).Value, args) };
}
}
return null;
}
private static SqlExpression VisitMemberAccess(MemberExpression memberExpression)
{
if (memberExpression.Expression != null && memberExpression.Expression.NodeType == ExpressionType.Parameter) {
var column = new SqlWhereColumn { Prefix = ((ParameterExpression)memberExpression.Expression).Name, Name = QueryTranslator.GetColumnName(memberExpression.Member) };
return column;
} else if (memberExpression.Expression != null && memberExpression.Expression is MemberExpression && ((MemberExpression)memberExpression.Expression).Expression.NodeType == ExpressionType.Parameter) {
var sql = new SqlWhereColumn { Prefix = ((MemberExpression)memberExpression.Expression).Member.Name, Name = QueryTranslator.GetColumnName(memberExpression.Member) };
return sql;
} else if (memberExpression.Expression != null && memberExpression.Expression is MemberExpression && ((MemberExpression)memberExpression.Expression).Expression.NodeType == ExpressionType.Constant) {
var lambda = Expression.Lambda(memberExpression);
var fn = lambda.Compile();
return Visit(Expression.Constant(fn.DynamicInvoke(null), memberExpression.Type));
} else if (memberExpression.Expression != null && memberExpression.Expression is MemberExpression && !(((MemberExpression)memberExpression.Expression).Expression.NodeType == ExpressionType.MemberAccess)) {
var sql = new SqlWhereColumn { Prefix = ((MemberExpression)memberExpression.Expression).Member.Name, Name = QueryTranslator.GetColumnName(memberExpression.Member) };
return sql;
} else {
var lambda = Expression.Lambda(memberExpression);
var fn = lambda.Compile();
return Visit(Expression.Constant(fn.DynamicInvoke(null), memberExpression.Type));
}
}
