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Using regex to capture a value in a text line

I have a text line and I need capture the value “Keyword” key.

In this sample the value is “ConquestImageDate”.

With my code below I can capture the value as ConquestImageDate”.

But it has a ‘”‘ on the end.

I know I can use a replace to get rid off it.

But, I´d like to do it in the regex.

let line =
  '(0008,0023) VERS="CQ"   VR="DA"   VM="1"    Keyword="ConquestImageDate"             Name="Conquest Image Date"';
const re = /Keyword="s*(S+)/;
m = re.exec(line);
console.log(m[1]);

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Answer

You are not matching the closing ", and as exec might yield null you can check for m first before indexing into it.

let line =
  '(0008,0023) VERS="CQ"   VR="DA"   VM="1"    Keyword="ConquestImageDate"             Name="Conquest Image Date"';
const re = /Keyword="s*(S+)"/;
m = re.exec(line);
if (m) {
  console.log(m[1]);
}

If there can also be unwanted whitespace chars at the end, you could making the S non greedy.

let line =
  '(0008,0023) VERS="CQ"   VR="DA"   VM="1"    Keyword="ConquestImageDate"             Name="Conquest Image Date"';
const re = /Keyword="s*(S*?)s*"/;
m = re.exec(line);
if (m) {
  console.log(m[1]);
}

You are matching Keyword which is singular, but if in any case you want to match spaces or newlines as well between the double quotes

bKeyword="s*([^"]*?)"

Regex demo

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