/// <summary> /// Constructor that allows the caller to specify file selection criteria. /// </summary> /// /// <remarks> /// <para> /// This constructor allows the caller to specify a set of criteria for selection of files. /// </para> /// /// <para> /// See <see cref="FileSelector.SelectionCriteria"/> for a description of the syntax of /// the selectionCriteria string. /// </para> /// </remarks> /// /// <param name="selectionCriteria">The criteria for file selection.</param> public FileSelector(String selectionCriteria) { if (!String.IsNullOrEmpty(selectionCriteria)) { _Criterion = _ParseCriterion(selectionCriteria); } }
private static SelectionCriterion _ParseCriterion(String s) { if (s == null) { return(null); } // shorthand for filename glob if (s.IndexOf(" ") == -1) { s = "name = " + s; } // inject spaces after open paren and before close paren string[] prPairs = { @"\((\S)", "( $1", @"(\S)\)", "$1 )", }; for (int i = 0; i + 1 < prPairs.Length; i += 2) { Regex rgx = new Regex(prPairs[i]); s = rgx.Replace(s, prPairs[i + 1]); } // split the expression into tokens string[] tokens = s.Trim().Split(' ', '\t'); if (tokens.Length < 3) { throw new ArgumentException(s); } SelectionCriterion current = null; LogicalConjunction pendingConjunction = LogicalConjunction.NONE; ParseState state; var stateStack = new System.Collections.Generic.Stack <ParseState>(); var critStack = new System.Collections.Generic.Stack <SelectionCriterion>(); stateStack.Push(ParseState.Start); for (int i = 0; i < tokens.Length; i++) { switch (tokens[i].ToLower()) { case "and": case "xor": case "or": state = stateStack.Peek(); if (state != ParseState.CriterionDone) { throw new ArgumentException(String.Join(" ", tokens, i, tokens.Length - i)); } if (tokens.Length <= i + 3) { throw new ArgumentException(String.Join(" ", tokens, i, tokens.Length - i)); } pendingConjunction = (LogicalConjunction)Enum.Parse(typeof(LogicalConjunction), tokens[i].ToUpper()); current = new CompoundCriterion { Left = current, Right = null, Conjunction = pendingConjunction }; stateStack.Push(state); stateStack.Push(ParseState.ConjunctionPending); critStack.Push(current); break; case "(": state = stateStack.Peek(); if (state != ParseState.Start && state != ParseState.ConjunctionPending && state != ParseState.OpenParen) { throw new ArgumentException(String.Join(" ", tokens, i, tokens.Length - i)); } if (tokens.Length <= i + 4) { throw new ArgumentException(String.Join(" ", tokens, i, tokens.Length - i)); } stateStack.Push(ParseState.OpenParen); break; case ")": state = stateStack.Pop(); if (stateStack.Peek() != ParseState.OpenParen) { throw new ArgumentException(String.Join(" ", tokens, i, tokens.Length - i)); } stateStack.Pop(); stateStack.Push(ParseState.CriterionDone); break; case "atime": case "ctime": case "mtime": if (tokens.Length <= i + 2) { throw new ArgumentException(String.Join(" ", tokens, i, tokens.Length - i)); } DateTime t; try { t = DateTime.ParseExact(tokens[i + 2], "yyyy-MM-dd-HH:mm:ss", null); } catch (FormatException) { t = DateTime.ParseExact(tokens[i + 2], "yyyy-MM-dd", null); } t = DateTime.SpecifyKind(t, DateTimeKind.Local).ToUniversalTime(); current = new TimeCriterion { Which = (WhichTime)Enum.Parse(typeof(WhichTime), tokens[i]), Operator = (ComparisonOperator)EnumUtil.Parse(typeof(ComparisonOperator), tokens[i + 1]), Time = t }; i += 2; stateStack.Push(ParseState.CriterionDone); break; case "length": case "size": if (tokens.Length <= i + 2) { throw new ArgumentException(String.Join(" ", tokens, i, tokens.Length - i)); } Int64 sz = 0; string v = tokens[i + 2]; if (v.ToUpper().EndsWith("K")) { sz = Int64.Parse(v.Substring(0, v.Length - 1)) * 1024; } else if (v.ToUpper().EndsWith("KB")) { sz = Int64.Parse(v.Substring(0, v.Length - 2)) * 1024; } else if (v.ToUpper().EndsWith("M")) { sz = Int64.Parse(v.Substring(0, v.Length - 1)) * 1024 * 1024; } else if (v.ToUpper().EndsWith("MB")) { sz = Int64.Parse(v.Substring(0, v.Length - 2)) * 1024 * 1024; } else if (v.ToUpper().EndsWith("G")) { sz = Int64.Parse(v.Substring(0, v.Length - 1)) * 1024 * 1024 * 1024; } else if (v.ToUpper().EndsWith("GB")) { sz = Int64.Parse(v.Substring(0, v.Length - 2)) * 1024 * 1024 * 1024; } else { sz = Int64.Parse(tokens[i + 2]); } current = new SizeCriterion { Size = sz, Operator = (ComparisonOperator)EnumUtil.Parse(typeof(ComparisonOperator), tokens[i + 1]) }; i += 2; stateStack.Push(ParseState.CriterionDone); break; case "filename": case "name": { if (tokens.Length <= i + 2) { throw new ArgumentException(String.Join(" ", tokens, i, tokens.Length - i)); } ComparisonOperator c = (ComparisonOperator)EnumUtil.Parse(typeof(ComparisonOperator), tokens[i + 1]); if (c != ComparisonOperator.NotEqualTo && c != ComparisonOperator.EqualTo) { throw new ArgumentException(String.Join(" ", tokens, i, tokens.Length - i)); } string m = tokens[i + 2]; // handle single-quoted filespecs (used to include spaces in filename patterns) if (m.StartsWith("'")) { int ix = i; if (!m.EndsWith("'")) { do { i++; if (tokens.Length <= i + 2) { throw new ArgumentException(String.Join(" ", tokens, ix, tokens.Length - ix)); } m += " " + tokens[i + 2]; } while (!tokens[i + 2].EndsWith("'")); } // trim off leading and trailing single quotes m = m.Substring(1, m.Length - 2); } current = new NameCriterion { MatchingFileSpec = m, Operator = c }; i += 2; stateStack.Push(ParseState.CriterionDone); } break; case "attributes": { if (tokens.Length <= i + 2) { throw new ArgumentException(String.Join(" ", tokens, i, tokens.Length - i)); } ComparisonOperator c = (ComparisonOperator)EnumUtil.Parse(typeof(ComparisonOperator), tokens[i + 1]); if (c != ComparisonOperator.NotEqualTo && c != ComparisonOperator.EqualTo) { throw new ArgumentException(String.Join(" ", tokens, i, tokens.Length - i)); } current = new AttributesCriterion { AttributeString = tokens[i + 2], Operator = c }; i += 2; stateStack.Push(ParseState.CriterionDone); } break; case "": // NOP stateStack.Push(ParseState.Whitespace); break; default: throw new ArgumentException("'" + tokens[i] + "'"); } state = stateStack.Peek(); if (state == ParseState.CriterionDone) { stateStack.Pop(); if (stateStack.Peek() == ParseState.ConjunctionPending) { while (stateStack.Peek() == ParseState.ConjunctionPending) { var cc = critStack.Pop() as CompoundCriterion; cc.Right = current; current = cc; // mark the parent as current (walk up the tree) stateStack.Pop(); // the conjunction is no longer pending state = stateStack.Pop(); if (state != ParseState.CriterionDone) { throw new ArgumentException("??"); } } } else { stateStack.Push(ParseState.CriterionDone); // not sure? } } if (state == ParseState.Whitespace) { stateStack.Pop(); } } return(current); }