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 /// /// 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 /// 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);
