dotnet use regex two samples

   

One sample is used to replace double quote from words which encapsulated by csvwriter ,

you know csv writer will take care of the double quote and comma and new line,

So if the words has comma or new line, csv writer will use default text qualifier double quote

Enclose them, sample :

Source : evan,yao CSV :"evan,yao"

And it will replace every double quote with two double quote.

Such as source data is evan,yao" csv: "evan,yao"""

So when we read csv words, we should replace the additional double quote,

I use c# and regex to do this, the following is two simple sample.

One is remove text qualifier, another one is replace demo.

Please enjoy.

using System;

using System.Text.RegularExpressions;

using System.IO;

using System.Collections;

   

public class test

{

public static string removeTextQualifier(string text)

{

string pattern = "^\"(?<word>.*)\"$";

Regex rgx = new Regex(pattern);

MatchCollection matches = rgx.Matches(text);

if(matches.Count>0)

return matches[0].Groups[0].Value.Replace("\"\"", "\"");

else

return text;

}

   

public static void regexReplaceDemo(int type)

{

string words = "letter alphabetical missing lack release " +

"penchant slack acryllic laundry cease";

if(type == 2)

words = @"select *from table1 left join table2 on table1.col1=table2.col2

right join t3 on table1.col2=t3.col1 full join t4 on t4.c1=t3.col2 where 1=1

and 2=2 or 3=3";

Console.WriteLine("Original words:");

Console.WriteLine(words);

Console.WriteLine();

Console.WriteLine("First Letter Capital words:");

Console.WriteLine(Regex.Replace(words, @"\w+", (m) => {

//change the first letter to capitalize

if(type == 1)

return m.Value[0].ToString().ToUpper() + m.Value.Substring(1);

else

{

string keywordslist = " select from where and or join left right full on ";

if(keywordslist.IndexOf(" " + m.Value + " ")>-1)

return m.Value.ToUpper();

else

return m.Value;

}

}));

}

   

public static void Main(string[] args)

{

regexReplaceDemo(1);

regexReplaceDemo(2);

}

 

}