private List<IAstNode> Tokenize(string str)
{
List<IAstNode> tokens = new List<IAstNode>();
// Used to make sure the string keeps shrinking on each iteration
int oldStringLen = str.Length + 1;
int currentLength = str.Length;
IAstNode preToken = new BaseAstNode();
// Keep processing the string until it is empty
while (currentLength > 0)
{
if (oldStringLen <= currentLength)
{
// If the string stopped shrinking, there was a problem
MessageBox.Show( @"SQL Parseエラーが発生しました。" + Environment.NewLine
+ @"入力SQLとともに管理者に問い合わせください。"
, @"重大なエラー [Line:" +preToken.StartLineNo + @"]"
, MessageBoxButtons.OK
, MessageBoxIcon.Error);
return tokens;
}
oldStringLen = currentLength;
IAstNode token = GetNextToken(str, preToken);
tokens.Add(token);
int tokenStrLength = token.OriginalValue.Length;
str = str.Substring(tokenStrLength);
currentLength -= tokenStrLength;
preToken = token;
}
tokens.Add(new BaseAstNode(preToken, string.Empty));
return tokens;
}
public virtual bool Visit(BaseAstNode node)
{
return true;
}
public virtual bool Transform(BaseAstNode node)
{
return true;
}