System.Xml.Xsl.XsltOld.Processor.GetSharedStringBuilder C# (CSharp) Method

        internal StringBuilder GetSharedStringBuilder() {
#if DEBUG
            Debug.Assert(! stringBuilderLocked);
#endif
            if (sharedStringBuilder == null) {
                sharedStringBuilder = new StringBuilder();
            }
            else {
                sharedStringBuilder.Length = 0;
            }
#if DEBUG
            stringBuilderLocked = true;
#endif
            return sharedStringBuilder;
        }

        internal string Evaluate(Processor processor, ActionFrame frame) {
            if (IsConstant) {
                Debug.Assert(constAvt != null);
                return constAvt;
            }
            else {
                Debug.Assert(processor != null && frame != null);

                StringBuilder builder = processor.GetSharedStringBuilder();

                for(int i = 0; i < events.Length; i ++) {
                    builder.Append(events[i].Evaluate(processor, frame));
                }
                processor.ReleaseSharedStringBuilder();
                return builder.ToString();
            }
        }