Csharp--read Csv file to DataTable

The information found on the Internet is not so great, many code at a glance to know that there is no overall consideration.

finally found a good, on the CodePlex , the man wrote a framework, too heavy.

Http://www.codeproject.com/Articles/9258/A-Fast-CSV-Reader

It's really nice.

I didn't have the patience to see his implementation, and he tried to write the following code to complete the reading of CSV.

Reference : http://msdn.microsoft.com/en-us/library/ae5bf541%28v=vs.90%29.aspx

Only two methods were written, and the organization was not particularly elegant.

When you use it, you only need to call READCSV2DT, the incoming parameter is a Boolean value for the file path and whether the first row is the Header.

the second method is to replace Csvwri theextra double quotes in the TER package.

 Public StaticDataTable Readcsv2dt (stringFileNameBOOLIsfirstlineheader) {DataTable dt=NewDataTable ();intQuotecount =0;intLastbyte =0;intb =0;D Atarow Dr=NULL;BOOLIsfirstline =true;intColindex =0; List<string> firstlinefields =Newlist<string>(); StringBuilder SB=NewStringBuilder ();using(FileStream fs =file.openread (filename)) { while((b = fs.) ReadByte ())! =-1){if(!isfirstline && Dr = =NULL) Dr=dt. NewRow ();if(b = =Ten&& Lastbyte = = -&& Quotecount%2==0)//One Row finished{if(!isfirstline) {Dr[colindex]=sb. ToString ();d T. Rows.Add (DR);}Else{if(isfirstlineheader) dt. Columns.Add (sb.) ToString ());ElseFirstlinefields. ADD (sb.) ToString ());//Build the table Strucureif(Isfirstline &&!)Isfirstlineheader) { for(inti =1; I <= firstlinefields. Count; i++) {dt. Columns.Add ("Col"+i);} Dr=dt. NewRow (); for(intj =0; J < Firstlinefields. Count; J + +) {Dr[j]=firstlinefields[j];} Dt. Rows.Add (DR);} Isfirstline=false;} Sb. Clear (); Quotecount=0; b=0;d R=NULL; Colindex=0; Lastbyte=0;}Else if(b = = -&& Quotecount%2==0)//One filed found stand for comma{if(isfirstline) {if(isfirstlineheader) dt. Columns.Add (Removetextqualifier (sb.) ToString ()));ElseFirstlinefields. ADD (Removetextqualifier (sb.) ToString ()));}ElseDr[colindex] =removetextqualifier (sb.) ToString ()); sb. Clear (); Colindex++;}Else{if(b = = the) quotecount++;//"Lastbyte=B;SB. Append (UnicodeEncoding.ASCII.GetString (New byte[] {byte. Parse (B.tostring ())}); }};returnDT;}  Public Static stringRemovetextqualifier (stringtext) {stringPattern ="^\ "(? <word>[\\s\\s]*) \" $"; Regex RGX=NewRegex (Pattern,regexoptions.multiline); Match m=RGX. Match (text);if(m.success)//return M.result ("($)"). Replace ("\" \ "", "\" ");returnm.groups["Word"]. Value.replace ("\"\"","\"");ElsereturnText. Replace ("\"\"","\"");}

: Test a file, the effect can also, and Excel opens with no differences displayed.

If you need to test, make sure you write the file is a valid csv file, otherwise please use Excel Save As, write your own file suffix is not true csv.

Csharp--read Csv file to DataTable