// 私有方法，对每一行进行分析
private void Analyse(String sourceTemp, StringBuilder resultString, int row)
{
int state = 0;
sourceTemp = sourceTemp.Trim();
char[] charArray = sourceTemp.ToCharArray();
for (int index = 0; charArray.Length != 0; index++)
{
// 分析注释
while (isAnnotation && sourceTemp.Length != 0)
{
// 多行注释结尾
if (sourceTemp[0] == '*' && sourceTemp[1] == '/')
{
isAnnotation = false;
// 过滤注释部分
sourceTemp = sourceTemp.Substring(2);
charArray = sourceTemp.ToCharArray();
}
else
{
// 逐个字符进行判断
sourceTemp = sourceTemp.Substring(1);
}
}
// 在过滤注释之后，判断源代码长度
if (sourceTemp.Length == 0)
{
break;
}
// 根据状态进行判断
switch (state)
{
case 0:
{
index = 0;
char ch = charArray[index];
// 过滤空格
while (ch == ' ')
{
sourceTemp = sourceTemp.Substring(1);
charArray = sourceTemp.ToCharArray();
ch = charArray[index];
}
if (ch == '/')
{
if (index + 1 == charArray.Length)
{
}
else if (charArray[index + 1] == '/')
{
// 单行注释，直接结束
charArray = "".ToCharArray();
break;
}
else if (charArray[index + 1] == '*')
{
// 多行注释
this.isAnnotation = true;
sourceTemp = sourceTemp.Substring(index + 2);
charArray = sourceTemp.ToCharArray();
state = 0;
index = 0;
break;
}
}
if (Char.IsLetter(ch) || ch == '_')
{
// 判断是否是字母或者_
state = 1;
}
else if (Char.IsDigit(ch))
{
// 判断是否是数字
state = 2;
}
else if (Utils.Include(Lexer.operators, ch))
{
// 操作符判断
state = 3;
}
else if (Utils.Include(Lexer.seperators, ch))
{
String s = Utils.CharToString(charArray, index + 1);
switch (ch)
{
case ',':
tokenList.Add(new Token("Comma", ch + "", row, true));
break;
case ';':
tokenList.Add(new Token("Semicolon", ch + "", row, true));
break;
case '(':
tokenList.Add(new Token("LeftTransparentheses", ch + "", row, true));
break;
case ')':
tokenList.Add(new Token("RightTransparentheses", ch + "", row, true));
break;
case '[':
tokenList.Add(new Token("ArrayLeftDelimiter", ch + "", row, true));
break;
case ']':
tokenList.Add(new Token("ArrayRightDelimiter", ch + "", row, true));
break;
case '{':
tokenList.Add(new Token("LeftBrace", ch + "", row, true));
break;
case '}':
tokenList.Add(new Token("RightBrace", ch + "", row, true));
break;
}
resultString.Append(s + "：Separator\n");
sourceTemp = sourceTemp.Substring(index + 1);
charArray = sourceTemp.ToCharArray();
state = 0;
index = 0;
}
else
{
tokenList.Add(new Token("Unrecognized word symbol", ch + "", row, false));
resultString.Append(ch + "：Unrecognized word symbol.\n");
sourceTemp = sourceTemp.Substring(index + 1);
charArray = sourceTemp.ToCharArray();
state = 0;
index = 0;
}
break;
}
// 标识符的判断
case 1:
{
char ch = ' ';
if (index < charArray.Length)
{
ch = charArray[index];
}
// 字母、数字、下划线
if (Char.IsLetter(ch) || ch == '_' || Char.IsDigit(ch))
{
state = 1;
}
else
{
String str = Utils.CharToString(charArray, index);
if (Utils.Include(reservedwords, str))
{
resultString.Append(str + "：Reserved words.\n");
switch (str)
{
case "int":
case "real":
tokenList.Add(new Token("VarialbeDeclarationWord", str, row, true));
break;
case "read":
tokenList.Add(new Token("Read", str, row, true));
break;
case "write":
tokenList.Add(new Token("Write", str, row, true));
break;
case "if":
tokenList.Add(new Token("If", str, row, true));
break;
case "else":
tokenList.Add(new Token("Else", str, row, true));
break;
case "while":
tokenList.Add(new Token("While", str, row, true));
break;
}
}
else if (charArray[index - 1] == '_')
{
tokenList.Add(new Token("The identifier can not end with underline", str, row, false));
resultString.Append(str + "：The identifier can not end with underline\n");
}
else
{
tokenList.Add(new Token("Identifier", str, row, true));
resultString.Append(str + "：Identifier\n");
}
sourceTemp = sourceTemp.Substring(index);
charArray = sourceTemp.ToCharArray();
state = 0;
index = 0;
}
break;
}
// 数字的判断
case 2:
{
char ch = ' ';
if (index < charArray.Length)
{
ch = charArray[index];
}
if (Char.IsDigit(ch) || ch == '.')
{
state = 2;
}
else
{
String str = Utils.CharToString(charArray, index);
try
{
double dou = Double.Parse(str);
resultString.Append(str + "：Constant\n");
int i = (int)dou;
if (dou == i)
{
tokenList.Add(new Token("Integer", str, row, true));
}
else
{
tokenList.Add(new Token("Real", str, row, true));
}
}
catch (Exception e)
{
tokenList.Add(new Token("The number format is wrong", str, row, false));
resultString.Append(str + "：The number format is wrong\n");
}
sourceTemp = sourceTemp.Substring(index);
charArray = sourceTemp.ToCharArray();
state = 0;
index = 0;
}
break;
}
// 操作符的判断
case 3:
{
char ch = ' ';
if (index < charArray.Length)
{
ch = charArray[index];
}
if (ch == '>' || ch == '=')
{
state = 3;
}
else
{
String str = Utils.CharToString(charArray, index);
if (str.Equals("="))
{
resultString.Append(str + "：Assignment operator\n");
tokenList.Add(new Token("Assignment", str, row, true));
}
else if (str.Length == 1 && !str.Equals("<") &&
!str.Equals(">"))
{
resultString.Append(str + "：Arithmetic operator\n");
tokenList.Add(new Token("Arithmetic", str, row, true));
}
else if (Utils.Include(Lexer.compare, str))
{
resultString.Append(str + "：Comparison operator\n");
tokenList.Add(new Token("Comparison", str, row, true));
}
else
{
tokenList.Add(new Token("Invalid operator", str, row, false));
resultString.Append(str + "：Invalid operator\n");
}
sourceTemp = sourceTemp.Substring(index);
charArray = sourceTemp.ToCharArray();
state = 0;
index = 0;
}
break;
}
}
}
}