Excel ファイルの各行のハッシュを計算することをお勧めします。次に、各行のハッシュを比較して、他のファイルのハッシュと一致するかどうかを確認できます (ソース コードのコメントを参照)。
また、Excel ファイルの内容を保存するためのクラスもいくつか用意しました。
using System.Security.Cryptography;
private void compare_btn_Click(object sender, EventArgs e)
{
string firstFile = firstExcel_txt.Text;
ExcelInfo file1 = ReadExcel(openFileDialog1);
string secondFile = secondExcel_txt.Text;
ExcelInfo file2 = ReadExcel(openFileDialog2);
CompareExcels(file1,file2) ;
}
public void CompareExcels(ExcelInfo fileA, ExcelInfo fileB)
{
foreach(ExcelRow rowA in fileA.excelRows)
{
//If the current hash of a row of fileA does not exists in fileB then it was removed
if(! fileB.ContainsHash(rowA.hash))
{
Console.WriteLine("Row removed" + rowA.ToString());
}
}
foreach(ExcelRow rowB in fileB.excelRows)
{
//If the current hash of a row of fileB does not exists in fileA then it was added
if(! fileA.ContainsHash(rowB.hash))
{
Console.WriteLine("Row added" + rowB.ToString());
}
}
}
public Class ExcelRow
{
public List<String> lstCells ;
public byte[] hash
public ExcelRow()
{
lstCells = new List<String>() ;
}
public override string ToString()
{
string resp ;
resp = string.Empty ;
foreach(string cellText in lstCells)
{
if(resp != string.Empty)
{
resp = resp + "," + cellText ;
}
else
{
resp = cellText ;
}
}
return resp ;
}
public void CalculateHash()
{
byte[] rowBytes ;
byte[] cellBytes ;
int pos ;
int numRowBytes ;
//Determine how much bytes are required to store a single excel row
numRowBytes = 0 ;
foreach(string cellText in lstCells)
{
numRowBytes += NumBytes(cellText) ;
}
//Allocate space to calculate the HASH of a single row
rowBytes= new byte[numRowBytes]
pos = 0 ;
//Concatenate the cellText of each cell, converted to bytes,into a single byte array
foreach(string cellText in lstCells)
{
cellBytes = GetBytes(cellText) ;
System.Buffer.BlockCopy(cellBytes, 0, rowBytes, pos, cellBytes.Length);
pos = cellBytes.Length ;
}
hash = new MD5CryptoServiceProvider().ComputeHash(rowBytes);
}
static int NumBytes(string str)
{
return str.Length * sizeof(char);
}
static byte[] GetBytes(string str)
{
byte[] bytes = new byte[NumBytes(str)];
System.Buffer.BlockCopy(str.ToCharArray(), 0, bytes, 0, bytes.Length);
return bytes;
}
}
public Class ExcelInfo
{
public List<ExcelRow> excelRows ;
public ExcelInfo()
{
excelRows = new List<ExcelRow>();
}
public bool ContainsHash(byte[] hashToLook)
{
bool found ;
found = false ;
foreach(ExcelRow eRow in excelRows)
{
found = EqualHash(eRow.hash, hashToLook) ;
if(found)
{
break ;
}
}
return found ;
}
public static EqualHash(byte[] hashA, byte[] hashB)
{
bool bEqual ;
int i ;
bEqual = false;
if (hashA.Length == hashB.Length)
{
i = 0;
while ((i < hashA.Length) && (hashA[i] == hashB[i]))
{
i++ ;
}
if (i == hashA.Length)
{
bEqual = true;
}
}
return bEqual ;
}
}
public ExcelInfo ReadExcel(OpenFileDialog openFileDialog)
{
var _excelFile = new ExcelQueryFactory(openFileDialog.FileName);
var _info = from c in _excelFile.WorksheetNoHeader() select c;
ExcelRow excelRow ;
ExcelInfo resp ;
resp = new ExcelInfo() ;
foreach (var item in _info)
{
excelRow = new ExcelRow() ;
//Add all the cells (with a for each)
excelRow.lstCells.Add(item.ElementAt(0));
excelRow.lstCells.Add(item.ElementAt(1));
....
//Add the last cell of the row
excelRow.lstCells.Add(item.ElementAt(N));
//Calculate the hash of the row
excelRow.CalculateHash() ;
//Add the row to the ExcelInfo object
resp.excelRows.Add(excelRow) ;
}
return resp ;
}