BN089-BS开发框架MVC4版/source20131023/Zephyr.Net/Zephyr.Utils/Document/Excel/NPOI/SS/Formula/EvaluationTracker.cs

这里只显示每个文件的开头 60 行。登录后可以解锁完整代码。

微信扫码关注公众号，代码整理好后第一时间通知你。

/* ====================================================================
   Licensed To the Apache Software Foundation (ASF) under one or more
   contributor license agreements.  See the NOTICE file distributed with
   this work for Additional information regarding copyright ownership.
   The ASF licenses this file To You under the Apache License, Version 2.0
   (the "License"); you may not use this file except in compliance with
   the License.  You may obtain a copy of the License at

       http://www.apache.org/licenses/LICENSE-2.0

   Unless required by applicable law or agreed To in writing, software
   distributed under the License is distributed on an "AS IS" BASIS,
   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   See the License for the specific language governing permissions and
   limitations under the License.
==================================================================== */

namespace Zephyr.Utils.NPOI.SS.Formula
{

    using System;
    using System.Collections;
    using Zephyr.Utils.NPOI.SS.Formula.Eval;
    

    /// <summary>
    /// Instances of this class keep track of multiple dependent cell evaluations due
    /// To recursive calls To <see cref="WorkbookEvaluator.Evaluate"/>
    /// The main purpose of this class is To detect an attempt To evaluate a cell
    /// that is already being evaluated. In other words, it detects circular
    /// references in spreadsheet formulas.
    /// </summary>
    /// <remarks>
    /// @author Josh Micich 
    /// </remarks>
    public class EvaluationTracker
    {
        // TODO - consider deleting this class and letting CellEvaluationFrame take care of itself
        private IList _evaluationFrames;
        private IList _currentlyEvaluatingCells;
        private EvaluationCache _cache;

        public EvaluationTracker(EvaluationCache cache)
        {
            _cache = cache;
            _evaluationFrames = new ArrayList();
            _currentlyEvaluatingCells = new ArrayList();
        }

        /**
         * Notifies this evaluation tracker that evaluation of the specified cell Is
         * about To start.<br/>
         *
         * In the case of a <c>true</c> return code, the caller should
         * continue evaluation of the specified cell, and also be sure To call
         * <c>endEvaluate()</c> when complete.<br/>
         *
         * In the case of a <c>null</c> return code, the caller should
         * return an evaluation result of
         * <c>ErrorEval.CIRCULAR_REF_ERROR</c>, and not call <c>endEvaluate()</c>.