//----------------------------------------------------------------------------------------
/// <summary>
/// Return a List of custom objects filtered by the filter parameter.
/// </summary>
/// <param name="filter">A FilterExpression representing the desired filter.</param>
/// <returns>A new List of custom objects with the requested Records</returns>
///
public List <T> SelectRecords <T>(FilterExpression filter)
where T : class, new()
{
return(SelectRecords <T>(filter, null, null, false));
}
//----------------------------------------------------------------------------------------
/// <summary>
/// Return a List of custom objects filtered by the filter parameter. Only the specified Fields
/// will be in the Table.
/// </summary>
/// <param name="filter">A FilterExpression representing the desired filter.</param>
/// <param name="fieldList">The desired fields to be in the returned Table</param>
/// <param name="orderByList">A list of one or more fields to order the returned table by,
/// or null for default order. If an orderByField is prefixed with "!", that field will sorted
/// in reverse order.</param>
/// <returns>A new List of custom objects with the requested Records and Fields ordered by the specified fields.</returns>
///
public List <T> SelectRecords <T>(FilterExpression filter, string[] fieldList, string[] orderByList)
where T : class, new()
{
return(SelectRecords <T>(filter, fieldList, orderByList, false));
}
static void parseExpression(string filter, ref int pos, FilterExpressionGroup parentSrchExpGrp)
{
ParseState state = ParseState.Left;
bool hasBracket = false,
inString = false,
isNot = false;
string fieldName = null;
object searchVal = null;
var sbTemp = new StringBuilder();
ComparisonOperatorEnum comparisonOp = ComparisonOperatorEnum.Equal;
MatchTypeEnum matchType = MatchTypeEnum.UseCase;
BoolOpEnum curBoolOp = BoolOpEnum.And;
int startPos = pos;
// skip past any leading spaces
while (pos < filter.Length && char.IsWhiteSpace(filter[pos]))
{
pos++;
}
for ( ; pos < filter.Length;)
{
//////////////////////////////////////////////////////////
#region Left
if (state == ParseState.Left)
{
if (filter[pos] == '[') // field names with ' ' in them must be wrapped with brackets
{
hasBracket = true;
pos++;
startPos = pos;
}
if (hasBracket)
{
// look for ending bracket
if (filter[pos] == ']')
{
fieldName = filter.Substring(startPos, pos - startPos).Trim();
pos++; // skip past bracket
}
}
else // no bracket - look for non-alpha
{
if (filter[pos] == '(')
{
// start of a new FilterExpressionGroup
pos++;
var newSrchExpGrp = new FilterExpressionGroup();
parentSrchExpGrp.Add(curBoolOp, newSrchExpGrp);
parseExpression(filter, ref pos, newSrchExpGrp);
state = ParseState.BoolOp;
}
else if (filter[pos] == '~') // eg. ~LastName
{
matchType = MatchTypeEnum.IgnoreCase;
}
else if (char.IsWhiteSpace(filter[pos]) ||
(!char.IsLetterOrDigit(filter[pos]) && filter[pos] != '_' && filter[pos] != '~'))
// field names with spaces in them must be wrapped with brackets
{
fieldName = filter.Substring(startPos, pos - startPos).Trim();
}
}
if (fieldName != null)
{
if (fieldName[0] == '~')
{
fieldName = fieldName.Substring(1);
matchType = MatchTypeEnum.IgnoreCase;
}
state = ParseState.CompareOp;
}
else
{
pos++;
}
}
#endregion Left
//////////////////////////////////////////////////////////
#region CompareOp
else if (state == ParseState.CompareOp)
{
// skip whitespace
while (pos < filter.Length && char.IsWhiteSpace(filter[pos]))
{
pos++;
}
if (char.IsLetter(filter[pos])) // REGEX
{
// should be CONTAINS, REGEX, IN or NOT
//if( pos + 4 >= filter.Length )
// throwInvalidFilterConstruct( filter, pos );
try
{
// NOT
if (char.ToUpper(filter[pos]) == 'N' && char.ToUpper(filter[pos + 1]) == 'O' &&
char.ToUpper(filter[pos + 2]) == 'T' && char.IsWhiteSpace(filter[pos + 3]))
{
pos += 3;
isNot = true;
continue;
}
// IN
else if (char.ToUpper(filter[pos]) == 'I' && char.ToUpper(filter[pos + 1]) == 'N' &&
(char.IsWhiteSpace(filter[pos + 2]) || filter[pos + 2] == '('))
{
pos += 2;
if (char.IsWhiteSpace(filter[pos])) // skip whitespace
{
while (pos < filter.Length && char.IsWhiteSpace(filter[pos]))
{
pos++;
}
if (filter[pos] != '(')
{
throwInvalidFilterConstruct(filter, pos - 2);
}
}
comparisonOp = ComparisonOperatorEnum.In;
}
// REGEX
else if (char.ToUpper(filter[pos]) == 'R' && char.ToUpper(filter[pos + 1]) == 'E' &&
char.ToUpper(filter[pos + 2]) == 'G' && char.ToUpper(filter[pos + 3]) == 'E' &&
char.ToUpper(filter[pos + 4]) == 'X' && char.IsWhiteSpace(filter[pos + 5]))
{
pos += 5;
comparisonOp = ComparisonOperatorEnum.Regex;
}
// CONTAINS
else if (char.ToUpper(filter[pos]) == 'C' && char.ToUpper(filter[pos + 1]) == 'O' &&
char.ToUpper(filter[pos + 2]) == 'N' && char.ToUpper(filter[pos + 3]) == 'T' &&
char.ToUpper(filter[pos + 4]) == 'A' && char.ToUpper(filter[pos + 5]) == 'I' &&
char.ToUpper(filter[pos + 6]) == 'N' && char.ToUpper(filter[pos + 7]) == 'S' &&
char.IsWhiteSpace(filter[pos + 8]))
{
pos += 8;
comparisonOp = ComparisonOperatorEnum.Contains;
}
else
{
throwInvalidFilterConstruct(filter, pos - 2);
}
}
catch (Exception ex)
{
throwInvalidFilterConstruct(filter, pos - 2);
}
}
// alternative way to specify ignore case search (other way is to prefix a fieldname with ~)
else if (filter[pos] == '~') // ~=
{
matchType = MatchTypeEnum.IgnoreCase;
if (++pos >= filter.Length)
{
throwInvalidFilterConstruct(filter, pos);
}
// next char must be =
if (filter[pos] != '=')
{
throwInvalidFilterConstruct(filter, pos);
}
comparisonOp = ComparisonOperatorEnum.Equal;
}
else if (filter[pos] == '!') // !=
{
if (++pos >= filter.Length)
{
throwInvalidFilterConstruct(filter, pos);
}
// next char must be =
if (filter[pos] != '=')
{
throwInvalidFilterConstruct(filter, pos);
}
comparisonOp = ComparisonOperatorEnum.Equal;
isNot = true;
}
else if (filter[pos] == '=')
{
comparisonOp = ComparisonOperatorEnum.Equal;
}
else if (filter[pos] == '<') // <, <= or <>
{
if (pos + 1 >= filter.Length)
{
throwInvalidFilterConstruct(filter, pos);
}
if (filter[pos + 1] == '>')
{
pos++;
comparisonOp = ComparisonOperatorEnum.Equal;
isNot = true;
}
else if (filter[pos + 1] == '=')
{
pos++;
comparisonOp = ComparisonOperatorEnum.LessThanOrEqual;
}
else
{
comparisonOp = ComparisonOperatorEnum.LessThan;
}
}
else if (filter[pos] == '>') // > or >=
{
if (pos + 1 >= filter.Length)
{
throwInvalidFilterConstruct(filter, pos);
}
if (filter[pos + 1] == '=')
{
pos++;
comparisonOp = ComparisonOperatorEnum.GreaterThanOrEqual;
}
else
{
comparisonOp = ComparisonOperatorEnum.GreaterThan;
}
}
else
{
throwInvalidFilterConstruct(filter, pos);
}
pos++;
state = ParseState.Right;
}
#endregion CompareOp
//////////////////////////////////////////////////////////
#region Right
else if (state == ParseState.Right)
{
if (comparisonOp == ComparisonOperatorEnum.In) //|| comparisonOp == EqualityEnum.NotIn )
{
// skip whitespace
while (pos < filter.Length && char.IsWhiteSpace(filter[pos]))
{
pos++;
}
// filter[pos] should look like this now: (val1, val2, val3)
// or like this: ('val1', 'val2', 'val3')
if (filter[pos] == '(')
{
pos++;
}
// find the end
int endPos = pos;
while (endPos < filter.Length && filter[endPos] != ')')
{
endPos++;
}
if (endPos >= filter.Length)
{
throw new FileDbException(string.Format(FileDbException.InvalidFilterConstruct, filter.Substring(pos)),
FileDbExceptionsEnum.InvalidFilterConstruct);
}
string inVals = filter.Substring(pos, endPos - pos);
searchVal = parseInVals(inVals, matchType);
pos = endPos;
}
else
{
if (!inString)
{
// skip whitespace only if we haven't found anything yet
if (sbTemp.Length == 0)
{
while (pos < filter.Length && char.IsWhiteSpace(filter[pos]))
{
pos++;
}
}
// look for end of ExpressionGroup
if (sbTemp.Length > 0 && (filter[pos] == ')' || char.IsWhiteSpace(filter[pos])))
{
// Expression completed
searchVal = sbTemp.ToString();
sbTemp.Length = 0;
var srchExp = new FilterExpression(fieldName, searchVal, comparisonOp, matchType, isNot);
parentSrchExpGrp.Add(curBoolOp, srchExp);
if (filter[pos] == ')')
{
return;
}
fieldName = null;
state = ParseState.BoolOp;
}
else if (sbTemp.Length == 0 && filter[pos] == '\'')
{
// just starting to get the value
inString = /*isString=*/ true;
}
else
{
sbTemp.Append(filter[pos]);
}
}
else // inString == true
{
if (filter[pos] == '\'')
{
//Debug.Assert( sbTemp.Length > 0 ); -- it could be empty, eg. myfield = ''
// if the next char is NOT another ' (escaped) then the string is completed
if ((pos + 1 < filter.Length) && filter[pos + 1] == '\'')
{
pos++;
}
else
{
inString = false;
searchVal = sbTemp.ToString();
sbTemp.Length = 0;
var srchExp = new FilterExpression(fieldName, searchVal, comparisonOp, matchType, isNot);
parentSrchExpGrp.Add(curBoolOp, srchExp);
fieldName = null;
state = ParseState.BoolOp;
goto Advance;
}
}
sbTemp.Append(filter[pos]);
}
}
Advance:
// advance
pos++;
}
#endregion Right
//////////////////////////////////////////////////////////
#region Next
else // if( state == ParseState.BoolOp )
{
Debug.Assert(state == ParseState.BoolOp);
if (sbTemp.Length == 0)
{
// skip whitespace
while (pos < filter.Length && char.IsWhiteSpace(filter[pos]))
{
pos++;
}
}
if (filter[pos] == ')')
{
return; // we must be finished
}
if (char.IsWhiteSpace(filter[pos]))
{
// we must be finished
if (sbTemp.Length == 0)
{
throw new FileDbException(string.Format(FileDbException.InvalidFilterConstruct, filter.Substring(pos)),
FileDbExceptionsEnum.InvalidFilterConstruct);
}
string sOp = sbTemp.ToString();
sbTemp.Length = 0;
if (string.Compare(sOp, "AND", StringComparison.OrdinalIgnoreCase) == 0)
{
curBoolOp = BoolOpEnum.And;
}
else if (string.Compare(sOp, "OR", StringComparison.OrdinalIgnoreCase) == 0)
{
curBoolOp = BoolOpEnum.Or;
}
else
{
throw new FileDbException(string.Format(FileDbException.InvalidFilterConstruct, filter.Substring(pos)),
FileDbExceptionsEnum.InvalidFilterConstruct);
}
state = ParseState.Left; // start over on next expression
// skip whitespace
while (pos < filter.Length && char.IsWhiteSpace(filter[pos]))
{
pos++;
}
// reset vars
startPos = pos;
hasBracket = false;
}
else
{
sbTemp.Append(filter[pos]);
pos++;
}
}
#endregion Next
} // for...
// did we just complete an Expression?
if (state == ParseState.Right)
{
if (comparisonOp != ComparisonOperatorEnum.In) //&& comparisonOp != EqualityEnum.NotIn )
{
searchVal = sbTemp.ToString();
if (!inString && string.Compare((string)searchVal, "null", StringComparison.OrdinalIgnoreCase) == 0)
{
searchVal = null;
}
sbTemp.Length = 0;
}
var srchExp = new FilterExpression(fieldName, searchVal, comparisonOp, matchType, isNot);
parentSrchExpGrp.Add(curBoolOp, srchExp);
}
}
