public static char ESCAPE_MARK = '\\'; //转义符号 public Element Read(ExpressionReader sr) { int index = sr.GetCurrentIndex(); var sb = new StringBuilder(); int b = sr.Read(); if (b == -1 || b != START_MARK) { throw new FormatException("不是有效的字符窜开始"); } while ((b = sr.Read()) != -1) { char c = (char)b; if (c == ESCAPE_MARK) {//遇到转义字符 c = GetEscapeValue((char)sr.Read()); } else if (c == END_MARK) {//遇到非转义的引号 return(new Element(sb.ToString(), index, ElementType.STRING)); } sb.Append(c); } throw new FormatException("不是有效的字符窜结束"); }
public Element Read(ExpressionReader sr) { int index = sr.GetCurrentIndex(); StringBuilder sb = new StringBuilder(); int b = sr.Read(); if (b == -1 || b != START_MARK) { throw new FormatException("不是有效的时间开始"); } while ((b = sr.Read()) != -1) { char c = (char)b; if (c == END_MARK) { return(new Element(FormatTime(sb.ToString()), index, ElementType.DATE)); } if (DATE_CHARS.IndexOf(c) == -1) { throw new FormatException("时间类型不能包函非法字符:" + c); } sb.Append(c); } throw new FormatException("不是有效的时间结束"); }
public static string DOUBLE_MARKS = "dD"; //double的结尾标志 public Element Read(ExpressionReader sr) { int index = sr.GetCurrentIndex(); string s = string.Empty; int b = -1; while ((b = sr.Read()) != -1) { char c = (char)b; if (NUMBER_CHARS.IndexOf(c) == -1) { if (LONG_MARKS.IndexOf(c) >= 0) { if (s.IndexOf(".") >= 0) {//有小数点 throw new FormatException("long类型不能有小数点"); } return(new Element(s.ToString(), index, ElementType.LONG)); } else if (FLOAT_MARKS.IndexOf(c) >= 0) { CheckDecimal(s); return(new Element(s.ToString(), index, ElementType.FLOAT)); } else if (DOUBLE_MARKS.IndexOf(c) >= 0) { CheckDecimal(s); return(new Element(s.ToString(), index, ElementType.DOUBLE)); } else { sr.Reset(); if (s.IndexOf(".") >= 0) {//没有结束标志,有小数点,为double CheckDecimal(s); return(new Element(s.ToString(), index, ElementType.DOUBLE)); } else {//没有结束标志,无小数点,为int return(new Element(s.ToString(), index, ElementType.INT)); } } } s += c; sr.Mark(0); } //读到结未 if (s.IndexOf(".") >= 0) {//没有结束标志,有小数点,为double CheckDecimal(s); return(new Element(s.ToString(), index, ElementType.DOUBLE)); } else {//没有结束标志,无小数点,为int return(new Element(s.ToString(), index, ElementType.INT)); } }
public static string SPLITOR_CHAR = "(),";//所有分割符 public Element Read(ExpressionReader sr) { int index = sr.GetCurrentIndex(); int b = sr.Read(); char c = (char)b; if (b == -1 || SPLITOR_CHAR.IndexOf(c) == -1) { throw new FormatException("不是有效的分割字符"); } return(new Element(c.ToString(), index, ElementType.SPLITOR)); }
public Element Read(ExpressionReader sr) { int index = sr.GetCurrentIndex(); var sb = new StringBuilder(); int b = sr.Read(); if (b == -1) { throw new FormatException("表达式已结束"); } char c = (char)b; sb.Append(c); if (IsOperatorWord(sb.ToString())) { if (sb.Length == 1) {//两个符号的运算符优先,如<=,不应该认为是<运算符 sr.Mark(0); b = sr.Read(); if (b != -1) { if (IsOperatorWord(sb.ToString() + (char)b)) { return(new Element(sb.ToString() + (char)b, index, ElementType.OPERATOR)); } } sr.Reset(); } return(new Element(sb.ToString(), index, ElementType.OPERATOR)); } while ((b = sr.Read()) != -1) { c = (char)b; sb.Append(c); if (IsOperatorWord(sb.ToString())) { return(new Element(sb.ToString(), index, ElementType.OPERATOR)); } if (VariableTypeReader.STOP_CHAR.IndexOf(c) >= 0) {//单词停止符 throw new FormatException("不是有效的运算符:" + sb.ToString()); } } throw new FormatException("不是有效的运算符结束"); }
public Element Read(ExpressionReader sr) { int index = sr.GetCurrentIndex(); string word = ReadWord(sr); if (TRUE_WORD.Equals(word) || FALSE_WORD.Equals(word)) { return(new Element(word, index, ElementType.BOOLEAN)); } else if (NULL_WORD.Equals(word)) { return(new Element(word, index, ElementType.NULL)); } else { return(new Element(word, index, ElementType.VARIABLE)); } }
public static char END_MARK = '('; //函数结束 /** * 从流中读取函数类型的ExpressionToken * @param sr * @return * @throws FormatException * @throws IOException */ public Element Read(ExpressionReader sr) { int index = sr.GetCurrentIndex(); var sb = new StringBuilder(); int b = sr.Read(); if (b == -1 || b != START_MARK) { throw new FormatException("不是有效的函数开始"); } bool readStart = true; while ((b = sr.Read()) != -1) { char c = (char)b; if (c == END_MARK) { if (sb.Length == 0) { throw new FormatException("函数名称不能为空"); } sr.Reset(); return(new Element(sb.ToString(), index, ElementType.FUNCTION)); } //if (!Character.isJavaIdentifierPart(c)) { // throw new FormatException("名称不能为非法字符:" + c); //} if (readStart) { //if (!Character.isJavaIdentifierStart(c)) { // throw new FormatException("名称开头不能为字符:" + c); //} readStart = false; } sb.Append(c); sr.Mark(0); } throw new FormatException("不是有效的函数结束"); }