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How do I match the entire line starting with MTA: ?

If I use:

console.log(result[2].split("Reporting-MTA:"))

I will still get the rest of the line, I want to match the entire line starting with MTA:

Thanks

Edit:

I want to match the line so I can read the lines BEFORE and AFTER that entire line. Now, I can only read the lines before and after the string "Reporting-MTA:"

Edit2:

2u+in.4eBZWuGLW.HROP9.bB7WHG
content-type: message/delivery-status

Reporting-MTA: dns; na-mm-outgoing-6102-bacon.iad6

Final-Recipient: rfc822;g
Action: failed
Status: 5.0.0 (permanent failure)
Diagnostic-Code: smtp; 5.1.2 - Bad destination host 'DNS Hard Error looking up tiagop.fdforg (MX):  NXDomain' (delivery attempts: 0)



/node/server.js:92
                console.log(r[1]);
               ^
TypeError: Cannot read property '1' of null

With this code:

console.log(result[2]);
        var r = result[2].match(/(.*)\r\nReporting-MTA\r\n(.*)/)
        console.log(r[1]);

How do I match the entire line starting with MTA: ?

If I use:

console.log(result[2].split("Reporting-MTA:"))

I will still get the rest of the line, I want to match the entire line starting with MTA:

Thanks

Edit:

I want to match the line so I can read the lines BEFORE and AFTER that entire line. Now, I can only read the lines before and after the string "Reporting-MTA:"

Edit2:

2u+in.4eBZWuGLW.HROP9.bB7WHG
content-type: message/delivery-status

Reporting-MTA: dns; na-mm-outgoing-6102-bacon.iad6.

Final-Recipient: rfc822;g
Action: failed
Status: 5.0.0 (permanent failure)
Diagnostic-Code: smtp; 5.1.2 - Bad destination host 'DNS Hard Error looking up tiagop.fdforg (MX):  NXDomain' (delivery attempts: 0)



/node/server.js:92
                console.log(r[1]);
               ^
TypeError: Cannot read property '1' of null

With this code:

console.log(result[2]);
        var r = result[2].match(/(.*)\r\nReporting-MTA\r\n(.*)/)
        console.log(r[1]);

• javascript
• regex
• node.js

Share Improve this question Follow edited Apr 15, 2011 at 9:40 donald asked Apr 15, 2011 at 9:16 donalddonald 23.8k4545 gold badges145145 silver badges224224 bronze badges

Add a ment  | 

4 Answers 4

Sorted by: Reset to default 4

If your input is from a text file then you need to look for the line breaks, so something like this...

It aint pretty but..

Test:

http://jsfiddle/wBR73/2/

Code:

var re = new RegExp(/((?:[\n\r]|.)*)(Reporting-MTA.*)((?:[\n\r]|.)*)/);
var arrMatches = strText.match(re);

Result:

arrMatches [1]   // Lines before a line Reporting-MTA:..$
arrMatches [2]   // Line started from Reporting-MTA:
arrMatches [3]   // Other lines after a line started from Reporting-MTA:

You can use match to do regular expression match and return an array of results to matches. This regex matches a pattern that starts (^) with MTA: and is followed by anything (.) zero or more times (*)...

var matches = result[2].match(/^MTA:.*/)
console.log(matches[0])

to capture groups within the match you can use brackets...

var matches = result[2].match(/^(MTA:)(.*)/)
console.log(matches[0]) // whole matched string
console.log(matches[1]) // first bracketed group - 'MTA:' in this case
console.log(matches[2]) // second bracketed group - the rest of the string in this case

Maybe it is easier to replace the line(s) you don't want

var replaced = result[2].replace(/.*Reporting-MTA:.*/gm,'')
console.log(replaced)

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