using System;
using System.Collections;
using System.Collections.Generic;
using System.Text;
namespace LumiSoft.Net
{
/// <summary>
/// This class provides usefull text methods.
/// </summary>
public class TextUtils
{
#region static method QuoteString
/// <summary>
/// Qoutes and escapes fishy(\") chars.
/// </summary>
/// <param name="text">Text to quote.</param>
/// <returns></returns>
public static string QuoteString(string text)
{
StringBuilder retVal = new StringBuilder();
for(int i=0;i<text.Length;i++){
char c = text[i];
if(c == '\\'){
retVal.Append("\\\\");
}
else if(c == '\"'){
retVal.Append("\\\"");
}
else{
retVal.Append(c);
}
}
return "\"" + retVal.ToString() + "\"";
}
#endregion
#region static method UnQuoteString
/// <summary>
/// Unquotes and unescapes escaped chars specified text. For example "xxx" will become to 'xxx', "escaped quote \"", will become to escaped 'quote "'.
/// </summary>
/// <param name="text">Text to unquote.</param>
/// <returns></returns>
public static string UnQuoteString(string text)
{
int startPosInText = 0;
int endPosInText = text.Length;
//--- Trim. We can't use standard string.Trim(), it's slow. ----//
for(int i=0;i<endPosInText;i++){
char c = text[i];
if(c == ' ' || c == '\t'){
startPosInText++;
}
else{
break;
}
}
for(int i=endPosInText-1;i>0;i--){
char c = text[i];
if(c == ' ' || c == '\t'){
endPosInText--;
}
else{
break;
}
}
//--------------------------------------------------------------//
// All text trimmed
if((endPosInText - startPosInText) <= 0){
return "";
}
// Remove starting and ending quotes.
if(text[startPosInText] == '\"'){
startPosInText++;
}
if(text[endPosInText - 1] == '\"'){
endPosInText--;
}
char[] chars = new char[endPosInText - startPosInText];
int posInChars = 0;
bool charIsEscaped = false;
for(int i=startPosInText;i<endPosInText;i++){
char c = text[i];
// Escaping char
if(!charIsEscaped && c == '\\'){
charIsEscaped = true;
}
// Escaped char
else if(charIsEscaped){
// TODO: replace \n,\r,\t,\v ???
chars[posInChars] = c;
posInChars++;
charIsEscaped = false;
}
// Normal char
else{
chars[posInChars] = c;
posInChars++;
charIsEscaped = false;
}
}
return new string(chars,0,posInChars);
}
#endregion
#region static method EscapeString
/// <summary>
/// Escapes specified chars in the specified string.
/// </summary>
/// <param name="text">Text to escape.</param>
/// <param name="charsToEscape">Chars to escape.</param>
public static string EscapeString(string text,char[] charsToEscape)
{
// Create worst scenario buffer, assume all chars must be escaped
char[] buffer = new char[text.Length * 2];
int nChars = 0;
foreach(char c in text){
foreach(char escapeChar in charsToEscape){
if(c == escapeChar){
buffer[nChars] = '\\';
nChars++;
break;
}
}
buffer[nChars] = c;
nChars++;
}
return new string(buffer,0,nChars);
}
#endregion
#region static method UnEscapeString
/// <summary>
/// Unescapes all escaped chars.
/// </summary>
/// <param name="text">Text to unescape.</param>
/// <returns></returns>
public static string UnEscapeString(string text)
{
// Create worst scenarion buffer, non of the chars escaped.
char[] buffer = new char[text.Length];
int nChars = 0;
bool escapedCahr = false;
foreach(char c in text){
if(!escapedCahr && c == '\\'){
escapedCahr = true;
}
else{
buffer[nChars] = c;
nChars++;
escapedCahr = false;
}
}
return new string(buffer,0,nChars);
}
#endregion
#region static method SplitQuotedString
/// <summary>
/// Splits string into string arrays. This split method won't split qouted strings, but only text outside of qouted string.
/// For example: '"text1, text2",text3' will be 2 parts: "text1, text2" and text3.
/// </summary>
/// <param name="text">Text to split.</param>
/// <param name="splitChar">Char that splits text.</param>
/// <returns></returns>
public static string[] SplitQuotedString(string text,char splitChar)
{
return SplitQuotedString(text,splitChar,false);
}
/// <summary>
/// Splits string into string arrays. This split method won't split qouted strings, but only text outside of qouted string.
/// For example: '"text1, text2",text3' will be 2 parts: "text1, text2" and text3.
/// </summary>
/// <param name="text">Text to split.</param>
/// <param name="splitChar">Char that splits text.</param>
/// <param name="unquote">If true, splitted parst will be unqouted if they are qouted.</param>
/// <returns></returns>
public static string[] SplitQuotedString(string text,char splitChar,bool unquote)
{
List<string> splitParts = new List<string>(); // Holds splitted parts
int startPos = 0;
bool inQuotedString = false; // Holds flag if position is quoted string or not
char lastChar = '0';
for(int i=0;i<text.Length;i++){
char c = text[i];
// Start/end quoted string area. Ingonre escaped \".
if(lastChar != '\\' && c == '\"'){
inQuotedString = !inQuotedString;
}
// Current char is split char and it isn't in quoted string, do split
if(!inQuotedString && c == splitChar){
// Add current currentSplitBuffer value to splitted parts list
if(unquote){
splitParts.Add(UnQuoteString(text.Substring(startPos,i - startPos)));
}
else{
splitParts.Add(text.Substring(startPos,i - startPos));
}
// Store new split part start position.
startPos = i + 1;
}
lastChar = c;
}
// Add last split part to splitted parts list
if(unquote){
splitParts.Add(UnQuoteString(text.Substring(startPos,text.Length - startPos)));
}
else{
splitParts.Add(text.Substring(startPos,text.Length - startPos));
}
return splitParts.ToArray();
}
#endregion
#region method QuotedIndexOf
/// <summary>
/// Gets first index of specified char. The specified char in quoted string is skipped.
/// Returns -1 if specified char doesn't exist.
/// </summary>
/// <param name="text">Text in what to check.</param>
/// <param name="indexChar">Char what index to get.</param>
/// <returns></returns>
public static int QuotedIndexOf(string text,char indexChar)
{
int retVal = -1;
bool inQuotedString = false; // Holds flag if position is quoted string or not
for(int i=0;i<text.Length;i++){
char c = text[i];
if(c == '\"'){
// Start/end quoted string area
inQuotedString = !inQuotedString;
}
// Current char is what index we want and it isn't in quoted string, return it's index
if(!inQuotedString && c == indexChar){
return i;
}
}
return retVal;
}
#endregion
#region static method SplitString
/// <summary>
/// Splits string into string arrays.
/// </summary>
/// <param name="text">Text to split.</param>
/// <param name="splitChar">Char Char that splits text.</param>
/// <returns></returns>
public static string[] SplitString(string text,char splitChar)
{
ArrayList splitParts = new ArrayList(); // Holds splitted parts
int lastSplitPoint = 0;
int textLength = text.Length;
for(int i=0;i<textLength;i++){
if(text[i] == splitChar){
// Add current currentSplitBuffer value to splitted parts list
splitParts.Add(text.Substring(lastSplitPoint,i - lastSplitPoint));
lastSplitPoint = i + 1;
}
}
// Add last split part to splitted parts list
if(lastSplitPoint <= textLength){
splitParts.Add(text.Substring(lastSplitPoint));
}
string[] retVal = new string[splitParts.Count];
splitParts.CopyTo(retVal,0);
return retVal;
}
#endregion
#region static method IsToken
/// <summary>
/// Gets if specified string is valid "token" value.
/// </summary>
/// <param name="value">String value to check.</param>
/// <returns>Returns true if specified string value is valid "token" value.</returns>
/// <exception cref="ArgumentNullException">Is raised if <b>value</b> is null.</exception>
public static bool IsToken(string value)
{
if(value == null){
throw new ArgumentNullException(value);
}
/* This syntax is taken from rfc 3261, but token must be universal so ... .
token = 1*(alphanum / "-" / "." / "!" / "%" / "*" / "_" / "+" / "`" / "'" / "~" )
alphanum = ALPHA / DIGIT
ALPHA = %x41-5A / %x61-7A ; A-Z / a-z
DIGIT = %x30-39 ; 0-9
*/
char[] tokenChars = new char[]{'-','.','!','%','*','_','+','`','\'','~'};
foreach(char c in value){
// We don't have letter or digit, so we only may have token char.
if(!((c >= 0x41 && c <= 0x5A) || (c >= 0x61 && c <= 0x7A) || (c >= 0x30 && c <= 0x39))){
bool validTokenChar = false;
foreach(char tokenChar in tokenChars){
if(c == tokenChar){
validTokenChar = true;
break;
}
}
if(!validTokenChar){
return false;
}
}
}
return true;
}
#endregion
}
}
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