I wrote this snip while ago for one of my oracle friends to break long running strings. Today I was in need of it again and I had to go through my library to find it. I am sure there is huge room for improvement. The job of the below code is to snip each paragraph using the max length into smaller strings.
public static string WrapText(string text, int maxLength)
{
// validate the incoming text
if (string.IsNullOrEmpty(text))
return text;
// break the string into smaller parts
string[] StringArray = System.Text.RegularExpressions.Regex.Split(
text,
"[\n]",
RegexOptions.Compiled RegexOptions.Multiline RegexOptions.Singleline RegexOptions.IgnoreCase);
// holds the string lines
List<string> StringLines = new List<string>();
// iterate through the array
foreach (string s in StringArray)
{
// the line is less then the allowed length
// add to the StringLines colleciton
if (s.Length <= maxLength)
StringLines.Add(s);
else
{
// longer string, so we use the start index to do our work
int StartIndex = 0;
// while loop breaking the long string
while (StartIndex <= s.Length)
{
// end index
int EndIndex = StartIndex + maxLength;
// trap for end index becoming longer than start index
if (EndIndex > s.Length)
{
// add to the StringLines colleciton
StringLines.Add(s.Substring(StartIndex, s.Length - StartIndex - 1));
break;
}
else
{
// character at end index position
string CharAtPosition = s[EndIndex].ToString();
// the character is not a space and not a (.) period
if (CharAtPosition != " " && CharAtPosition != ".")
{
// back track to find a space
// it is expected there will be a space at the end of a sentence
while (CharAtPosition != " " && EndIndex >= 0)
{
// trap in case it is a long word/url or something
if (EndIndex == 0)
break;
EndIndex = EndIndex - 1;
CharAtPosition = s[EndIndex].ToString();
}
// if end index becomes 0, then we need to take
// whatever is available
if (EndIndex == 0)
EndIndex = s.Length - 1;
}
// calculate the length we are going to take the snip and make the snip
int SubEndLenth = EndIndex - StartIndex;
StringLines.Add(s.Substring(StartIndex, SubEndLenth));
// increment the start index for the next request
StartIndex += SubEndLenth;
// if char at the position was a space, increment the start index by 1
// this is necessary becuase the next line will end up with a space as the starting charcter
if (CharAtPosition == " ") StartIndex += 1;
}
}
}
}
return string.Join("\r\n", StringLines.ToArray());
}
