CreatenewtoolforCSV-创新互联

public class CsvFileStream
    {
        TextReader stream;
bool EOS = false;
bool EOL = false;

public CsvFileStream(TextReader s)
        {
            stream= s;
        }

public string[] GetNextRow()
        {
            ArrayList row= new ArrayList();
while (true)
            {
string item = GetNextItem();
if (item == null)
return row.Count == 0 ? null : (string[])row.ToArray(typeof(string));
                row.Add(item);
            }
        }

string GetNextItem()
        {
if (EOL)
            {
// previous item was last in line, start new line                EOL = false;
return null;
            }

bool quoted = false;
bool predata = true;
bool postdata = false;
            StringBuilder sb= new StringBuilder();

while (true)
            {
char c = GetNextChar(true);
if (EOS)
return sb.Length > 0 ? sb.ToString() : null;

if ((postdata || !quoted) && c == ',')
// end of item, return   return sb.ToString();

if ((predata || postdata || !quoted) && (c == 'x0A' || c == 'x0D'))
                {
// we are at the end of the line, eat newline characters and exit                    EOL = true;
if (c == 'x0D' && GetNextChar(false) == 'x0A')
// new line sequence is 0D0A                        GetNextChar(true);
return sb.ToString();
                }

if (predata && c == ' ')
// whitespace preceeding data, discard   continue;

if (predata && c == '"')
                {
// quoted data is starting                    quoted = true;
                    predata= false;
continue;
                }

if (predata)
                {
// data is starting without quotes                    predata = false;
                    sb.Append(c);
continue;
                }

if (c == '"' && quoted)
                {
if (GetNextChar(false) == '"')
// double quotes within quoted string means add a quote                        sb.Append(GetNextChar(true));
else // end-quote reached                        postdata = true;
continue;
                }

// all cases covered, character must be data                sb.Append(c);
            }
        }

char[] buffer = new char[4096];
int pos = 0;
int length = 0;

char GetNextChar(bool eat)
        {
if (pos >= length)
            {
                length= stream.ReadBlock(buffer, 0, buffer.Length);
if (length == 0)
                {
                    EOS= true;
return '';
                }
                pos= 0;
            }
if (eat)
return buffer[pos++];
else  return buffer[pos];
        }
    }

CsvFileWriter.cs

public class CsvFileWriter
    {
private ArrayList rowAL;   //行链表,CSV文件的每一行就是一个链   private string fileName;  //文件名   private Encoding encoding;  //编码   public CsvFileWriter()
        {
this.rowAL = new ArrayList();
this.fileName = "";
this.encoding = Encoding.Default;
        }

/// 
   /// 
   /// 
   /// 文件名,包括文件路径   public CsvFileWriter(string fileName)
        {
this.rowAL = new ArrayList();
this.fileName = fileName;
this.encoding = Encoding.Default;
        }

/// 
   /// 
   /// 
   /// 文件名,包括文件路径   /// 文件编码   public CsvFileWriter(string fileName, Encoding encoding)
        {
this.rowAL = new ArrayList();
this.fileName = fileName;
this.encoding = encoding;
        }

/// 
   /// row:行,row = 1代表第一行
/// col:列,col = 1代表第一列
/// 
   public string this[int row, int col]
        {
set
            {
//对行进行判断  if (row <= 0)
                {
throw new Exception("行数不能小于0");
                }
else if (row > this.rowAL.Count) //如果当前列链的行数不够，要补齐                {
for (int i = this.rowAL.Count + 1; i <= row; i++)
                    {
this.rowAL.Add(new ArrayList());
                    }
                }
else
                {
                }
//对列进行判断  if (col <= 0)
                {
throw new Exception("列数不能小于0");
                }
else
                {
                    ArrayList colTempAL= (ArrayList)this.rowAL[row - 1];

//扩大长度   if (col > colTempAL.Count)
                    {
for (int i = colTempAL.Count; i <= col; i++)
                        {
                            colTempAL.Add("");
                        }
                    }
this.rowAL[row - 1] = colTempAL;
                }
//赋值                ArrayList colAL = (ArrayList)this.rowAL[row - 1];

                colAL[col- 1] = value;
this.rowAL[row - 1] = colAL;
            }
        }

/// 
   /// 文件名,包括文件路径
/// 
   public string FileName
        {
set
            {
this.fileName = value;
            }
        }

/// 
   /// 文件编码
/// 
   public Encoding FileEncoding
        {
set
            {
this.encoding = value;
            }
        }

/// 
   /// 获取当前大行
/// 
   public int CurMaxRow
        {
get
            {
return this.rowAL.Count;
            }
        }

/// 
   /// 获取大列
/// 
   public int CurMaxCol
        {
get
            {
int maxCol;

                maxCol= 0;
for (int i = 0; i < this.rowAL.Count; i++)
                {
                    ArrayList colAL= (ArrayList)this.rowAL[i];

                    maxCol= (maxCol > colAL.Count) ? maxCol : colAL.Count;
                }

return maxCol;
            }
        }

/// 
   /// 添加表数据到CSV文件中
/// 
   /// 表数据   /// 从第几列开始,beginCol = 1代表第一列   public void AddData(DataTable dataDT, int beginCol)
        {
if (dataDT == null)
            {
throw new Exception("需要添加的表数据为空");
            }
int curMaxRow;

            curMaxRow= this.rowAL.Count;
for (int i = 0; i < dataDT.Rows.Count; i++)
            {
for (int j = 0; j < dataDT.Columns.Count; j++)
                {
this[curMaxRow + i + 1, beginCol + j] = dataDT.Rows[i][j].ToString();
                }
            }
        }

/// 
   /// 保存数据,如果当前硬盘中已经存在文件名一样的文件，将会覆盖
/// 
   public void Save()
        {
//对数据的有效性进行判断 if (this.fileName == null)
            {
throw new Exception("缺少文件名");
            }
else if (File.Exists(this.fileName))
            {
                File.Delete(this.fileName);
            }
if (this.encoding == null)
            {
this.encoding = Encoding.Default;
            }
            System.IO.StreamWriter sw= new StreamWriter(this.fileName, false, this.encoding);

for (int i = 0; i < this.rowAL.Count; i++)
            {
                sw.WriteLine(ConvertToSaveLine((ArrayList)this.rowAL[i]));
            }

            sw.Close();
        }

/// 
   /// 保存数据,如果当前硬盘中已经存在文件名一样的文件，将会覆盖
/// 
   /// 文件名,包括文件路径   public void Save(string fileName)
        {
this.fileName = fileName;
            Save();
        }

/// 
   /// 保存数据,如果当前硬盘中已经存在文件名一样的文件，将会覆盖
/// 
   /// 文件名,包括文件路径   /// 文件编码   public void Save(string fileName, Encoding encoding)
        {
this.fileName = fileName;
this.encoding = encoding;
            Save();
        }

/// 
   /// 转换成保存行
/// 
   /// 一行   ///    private string ConvertToSaveLine(ArrayList colAL)
        {
string saveLine;

            saveLine= "";
for (int i = 0; i < colAL.Count; i++)
            {
                saveLine+= ConvertToSaveCell(colAL[i].ToString());
//格子间以逗号分割  if (i < colAL.Count - 1)
                {
                    saveLine+= ",";
                }
            }

return saveLine;
        }

/// 
   /// 字符串转换成CSV中的格子
/// 双引号转换成两个双引号，然后首尾各加一个双引号
/// 这样就不需要考虑逗号及换行的问题
/// 
   /// 格子内容   ///    private string ConvertToSaveCell(string cell)
        {
            cell= cell.Replace(""","""");

return """ + cell + """;
//return "";        }
    }

CsvFileReader.cs

public class CsvFileReader
    {
public static DataTable Parse(string data, bool headers)
        {
return Parse(new StringReader(data), headers);
        }

public static DataTable Parse(string data)
        {
return Parse(new StringReader(data));
        }

public static DataTable Parse(TextReader stream)
        {
return Parse(stream, false);
        }

public static DataTable Parse(TextReader stream, bool headers)
        {
            DataTable table= new DataTable();

            CsvFileStream csv= new CsvFileStream(stream);
string[] row = csv.GetNextRow();
if (row == null) return null;

if (headers)
            {
foreach (string header in row)
                {
if (header != null && header.Length > 0 && !table.Columns.Contains(header))
                        table.Columns.Add(header,typeof(string));
else
                        table.Columns.Add(GetNextColumnHeader(table),typeof(string));
                }
                row= csv.GetNextRow();
            }

while (row != null)
            {
while (row.Length > table.Columns.Count)
                    table.Columns.Add(GetNextColumnHeader(table),typeof(string));
                table.Rows.Add(row);
                row= csv.GetNextRow();
            }
return table;
        }

static string GetNextColumnHeader(DataTable table)
        {
int c = 1;
while (true)
            {
string h = "Column" + c++;
if (!table.Columns.Contains(h))
return h;
            }
        }
    }

eg.

TextReader reader = new StreamReader(@"D:	est.csv");
DataTable dt= CsvFileReader.Parse(reader, false);