I have a C# regular expression to match author names in a text document that is written as:
"author":"AUTHOR'S NAME"
The regex is as follows:
new Regex("\"author\":\"[A-Za-z0-9]*\\s?[A-Za-z0-9]*")
This returns "author":"AUTHOR'S NAME. However, I don't want the quotation marks or the word Author before. I just want the name.
Could anyone help me get the expected value please?
Use regex groups to get a part of the string. ( ) acts as a capture group and can be accessed by the .Groups field.
.Groups[0] matches the whole string
.Groups[1] matches the first group (and so on)
string pattern = "\"author\":\"([A-Za-z0-9]*\\s?[A-Za-z0-9]*)\"";
var match = Regex.Match("\"author\":\"Name123\"", pattern);
string authorName = match.Groups[1];
You can also use look-around approach to only get a match value:
var txt = "\"author\":\"AUTHOR'S NAME\"";
var rgx = new Regex(@"(?<=""author"":"")[^""]+(?="")");
var result = rgx.Match(txt).Value;
My regex yields 555,020 iterations per second speed with this input string, which should suffice.
result will be AUTHOR'S NAME.
(?<="author":") checks if we have "author":" before the match, [^"]+ looks safe since you only want to match alphanumerics and space between the quotes, and (?=") is checking the trailing quote.
:, we can enhance the look-behind as @"(?<=""author""\s*:\s*"")[^""]+(?="")".
'inO'Connorand it only allows for exactly one space, no hyphens, no foreign characters etc. I don't know your usecase, but if you know the author name is going to be enclosed within the quotes, you would get away with just accepting anything that isn't a double quotes:\"author\":\"([^\"]+)\".