用C#写的读写CSV文件

时间:2021-02-02 14:34:08

用C#写的读取CSV文件的源代码

CSV文件的格子中包含逗号,引号,换行等,都能轻松读取,而且可以把数据转化成DATATABLE格式

using System;
using System.Text;
using System.Collections;
using System.IO;
using System.Data;
using System.Text.RegularExpressions;
using System.Diagnostics; namespace CsvLib
{
#region 类说明信息 /// <summary>
/// <DL>
/// <DT><b>读CSV文件类,读取指定的CSV文件,可以导出DataTable</b></DT>
/// <DD>
/// <UL>
/// </UL>
/// </DD>
/// </DL>
/// <Author>yangzhihong</Author>
/// <CreateDate>2006/01/16</CreateDate>
/// <Company></Company>
/// <Version>1.0</Version>
/// </summary>
#endregion
public class CsvStreamReader
{
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 CsvStreamReader()
{
this.rowAL = new ArrayList();
this.fileName = "";
this.encoding = Encoding.Default;
} /// <summary>
///
/// </summary>
/// <param name="fileName">文件名,包括文件路径</param>
public CsvStreamReader(string fileName)
{
this.rowAL = new ArrayList();
this.fileName = fileName;
this.encoding = Encoding.Default;
LoadCsvFile();
} /// <summary>
///
/// </summary>
/// <param name="fileName">文件名,包括文件路径</param>
/// <param name="encoding">文件编码</param>
public CsvStreamReader(string fileName,Encoding encoding)
{
this.rowAL = new ArrayList();
this.fileName = fileName;
this.encoding = encoding;
LoadCsvFile();
} /// <summary>
/// 文件名,包括文件路径
/// </summary>
public string FileName
{
set
{
this.fileName = value;
LoadCsvFile();
}
} /// <summary>
/// 文件编码
/// </summary> public Encoding FileEncoding
{
set
{
this.encoding = value;
}
} /// <summary>
/// 获取行数
/// </summary>
public int RowCount
{
get
{
return this.rowAL.Count;
}
} /// <summary>
/// 获取列数
/// </summary>
public int ColCount
{
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;
}
} /// <summary>
/// 获取某行某列的数据 /// row:行,row = 1代表第一行 /// col:列,col = 1代表第一列
/// </summary>
public string this[int row,int col]
{
get
{
//数据有效性验证 CheckRowValid(row);
CheckColValid(col);
ArrayList colAL = (ArrayList) this.rowAL[row-1]; //如果请求列数据大于当前行的列时,返回空值 if (colAL.Count < col)
{
return "";
} return colAL[col-1].ToString();
}
} /// <summary>
/// 根据最小行,最大行,最小列,最大列,来生成一个DataTable类型的数据 /// 行等于1代表第一行 /// 列等于1代表第一列 /// maxrow: -1代表最大行
/// maxcol: -1代表最大列
/// </summary>
public DataTable this[int minRow,int maxRow,int minCol,int maxCol]
{
get
{
//数据有效性验证 CheckRowValid(minRow);
CheckMaxRowValid(maxRow);
CheckColValid(minCol);
CheckMaxColValid(maxCol);
if (maxRow == -1)
{
maxRow = RowCount;
}
if (maxCol == -1)
{
maxCol = ColCount;
}
if (maxRow < minRow)
{
throw new Exception("最大行数不能小于最小行数");
}
if (maxCol < minCol)
{
throw new Exception("最大列数不能小于最小列数");
}
DataTable csvDT = new DataTable();
int i;
int col;
int row; //增加列 for (i = minCol;i <= maxCol;i++)
{
csvDT.Columns.Add(i.ToString());
}
for (row = minRow;row <= maxRow;row++)
{
DataRow csvDR = csvDT.NewRow(); i = 0;
for (col = minCol;col <=maxCol;col++)
{
csvDR[i] = this[row,col];
i++;
}
csvDT.Rows.Add(csvDR);
} return csvDT;
}
} /// <summary>
/// 检查行数是否是有效的 /// </summary>
/// <param name="col"></param>
private void CheckRowValid(int row)
{
if (row <= 0)
{
throw new Exception("行数不能小于0");
}
if (row > RowCount)
{
throw new Exception("没有当前行的数据");
}
} /// <summary>
/// 检查最大行数是否是有效的 /// </summary>
/// <param name="col"></param>
private void CheckMaxRowValid(int maxRow)
{
if (maxRow <= 0 && maxRow != -1)
{
throw new Exception("行数不能等于0或小于-1");
}
if (maxRow > RowCount)
{
throw new Exception("没有当前行的数据");
}
} /// <summary>
/// 检查列数是否是有效的 /// </summary>
/// <param name="col"></param>
private void CheckColValid(int col)
{
if (col <= 0)
{
throw new Exception("列数不能小于0");
}
if (col > ColCount)
{
throw new Exception("没有当前列的数据");
}
} /// <summary>
/// 检查检查最大列数是否是有效的 /// </summary>
/// <param name="col"></param>
private void CheckMaxColValid(int maxCol)
{
if (maxCol <= 0 && maxCol != -1)
{
throw new Exception("列数不能等于0或小于-1");
}
if (maxCol > ColCount)
{
throw new Exception("没有当前列的数据");
}
} /// <summary>
/// 载入CSV文件
/// </summary>
private void LoadCsvFile()
{
//对数据的有效性进行验证 if (this.fileName == null)
{
throw new Exception("请指定要载入的CSV文件名");
}
else if (!File.Exists(this.fileName))
{
throw new Exception("指定的CSV文件不存在");
}
else
{
}
if (this.encoding == null)
{
this.encoding = Encoding.Default;
} StreamReader sr = new StreamReader(this.fileName,this.encoding);
string csvDataLine; csvDataLine = "";
while (true)
{
string fileDataLine; fileDataLine = sr.ReadLine();
if (fileDataLine == null)
{
break;
}
if (csvDataLine == "")
{
csvDataLine = fileDataLine;//GetDeleteQuotaDataLine(fileDataLine);
}
else
{
csvDataLine += "/r/n" + fileDataLine;//GetDeleteQuotaDataLine(fileDataLine);
}
//如果包含偶数个引号,说明该行数据中出现回车符或包含逗号
if (!IfOddQuota(csvDataLine))
{
AddNewDataLine(csvDataLine);
csvDataLine = "";
}
}
sr.Close();
//数据行出现奇数个引号
if (csvDataLine.Length > 0)
{
throw new Exception("CSV文件的格式有错误");
}
} /// <summary>
/// 获取两个连续引号变成单个引号的数据行
/// </summary>
/// <param name="fileDataLine">文件数据行</param>
/// <returns></returns>
private string GetDeleteQuotaDataLine(string fileDataLine)
{
return fileDataLine.Replace("/"/"","/"");
} /// <summary>
/// 判断字符串是否包含奇数个引号
/// </summary>
/// <param name="dataLine">数据行</param>
/// <returns>为奇数时,返回为真;否则返回为假</returns>
private bool IfOddQuota(string dataLine)
{
int quotaCount;
bool oddQuota; quotaCount = 0;
for (int i = 0;i < dataLine.Length;i++)
{
if (dataLine[i] == '/"')
{
quotaCount++;
}
} oddQuota = false;
if (quotaCount % 2 == 1)
{
oddQuota = true;
} return oddQuota;
} /// <summary>
/// 判断是否以奇数个引号开始 /// </summary>
/// <param name="dataCell"></param>
/// <returns></returns>
private bool IfOddStartQuota(string dataCell)
{
int quotaCount;
bool oddQuota; quotaCount = 0;
for (int i = 0;i < dataCell.Length;i++)
{
if (dataCell[i] == '/"')
{
quotaCount++;
}
else
{
break;
}
} oddQuota = false;
if (quotaCount % 2 == 1)
{
oddQuota = true;
} return oddQuota;
} /// <summary>
/// 判断是否以奇数个引号结尾
/// </summary>
/// <param name="dataCell"></param>
/// <returns></returns>
private bool IfOddEndQuota(string dataCell)
{
int quotaCount;
bool oddQuota; quotaCount = 0;
for (int i = dataCell.Length -1;i >= 0;i--)
{
if (dataCell[i] == '/"')
{
quotaCount++;
}
else
{
break;
}
} oddQuota = false;
if (quotaCount % 2 == 1)
{
oddQuota = true;
} return oddQuota;
} /// <summary>
/// 加入新的数据行 /// </summary>
/// <param name="newDataLine">新的数据行</param>
private void AddNewDataLine(string newDataLine)
{
Debug.WriteLine("NewLine:" + newDataLine); //return; ArrayList colAL = new ArrayList();
string[] dataArray = newDataLine.Split(',');
bool oddStartQuota; //是否以奇数个引号开始 string cellData; oddStartQuota = false;
cellData = "";
for (int i = 0 ;i < dataArray.Length;i++)
{
if (oddStartQuota)
{
//因为前面用逗号分割,所以要加上逗号
cellData += "," + dataArray[i];
//是否以奇数个引号结尾
if (IfOddEndQuota(dataArray[i]))
{
colAL.Add(GetHandleData(cellData));
oddStartQuota = false;
continue;
}
}
else
{
//是否以奇数个引号开始 if (IfOddStartQuota(dataArray[i]))
{
//是否以奇数个引号结尾,不能是一个双引号,并且不是奇数个引号 if (IfOddEndQuota(dataArray[i]) && dataArray[i].Length > 2 && !IfOddQuota(dataArray[i]))
{
colAL.Add(GetHandleData(dataArray[i]));
oddStartQuota = false;
continue;
}
else
{ oddStartQuota = true;
cellData = dataArray[i];
continue;
}
}
else
{
colAL.Add(GetHandleData(dataArray[i]));
}
}
}
if (oddStartQuota)
{
throw new Exception("数据格式有问题");
}
this.rowAL.Add(colAL);
} /// <summary>
/// 去掉格子的首尾引号,把双引号变成单引号 /// </summary>
/// <param name="fileCellData"></param>
/// <returns></returns>
private string GetHandleData(string fileCellData)
{
if (fileCellData == "")
{
return "";
}
if (IfOddStartQuota(fileCellData))
{
if (IfOddEndQuota(fileCellData))
{
return fileCellData.Substring(1,fileCellData.Length-2).Replace("/"/"","/""); //去掉首尾引号,然后把双引号变成单引号
}
else
{
throw new Exception("数据引号无法匹配" + fileCellData);
}
}
else
{
//考虑形如"" """" """"""
if (fileCellData.Length >2 && fileCellData[0] == '/"')
{
fileCellData = fileCellData.Substring(1,fileCellData.Length-2).Replace("/"/"","/""); //去掉首尾引号,然后把双引号变成单引号
}
} return fileCellData;
}
}
} using System;
using System.Text;
using System.Collections;
using System.IO;
using System.Data; namespace CsvLib
{
#region 类说明信息
/// <summary>
/// <DL>
/// <DT><b>写CSV文件类,首先给CSV文件赋值,最后通过Save方法进行保存操作</b></DT>
/// <DD>
/// <UL>
/// </UL>
/// </DD>
/// </DL>
/// <Author>yangzhihong</Author>
/// <CreateDate>2006/01/16</CreateDate>
/// <Company></Company>
/// <Version>1.0</Version>
/// </summary>
#endregion
public class CsvStreamWriter
{
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 CsvStreamWriter()
{
this.rowAL = new ArrayList();
this.fileName = "";
this.encoding = Encoding.Default;
} /// <summary>
///
/// </summary>
/// <param name="fileName">文件名,包括文件路径</param>
public CsvStreamWriter(string fileName)
{
this.rowAL = new ArrayList();
this.fileName = fileName;
this.encoding = Encoding.Default;
} /// <summary>
///
/// </summary>
/// <param name="fileName">文件名,包括文件路径</param>
/// <param name="encoding">文件编码</param>
public CsvStreamWriter(string fileName,Encoding encoding)
{
this.rowAL = new ArrayList();
this.fileName = fileName;
this.encoding = encoding;
} /// <summary>
/// row:行,row = 1代表第一行
/// col:列,col = 1代表第一列
/// </summary>
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;
}
} /// <summary>
/// 文件名,包括文件路径
/// </summary>
public string FileName
{
set
{
this.fileName = value;
}
} /// <summary>
/// 文件编码
/// </summary> public Encoding FileEncoding
{
set
{
this.encoding = value;
}
} /// <summary>
/// 获取当前最大行
/// </summary>
public int CurMaxRow
{
get
{
return this.rowAL.Count;
}
} /// <summary>
/// 获取最大列
/// </summary>
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;
}
} /// <summary>
/// 添加表数据到CSV文件中
/// </summary>
/// <param name="dataDT">表数据</param>
/// <param name="beginCol">从第几列开始,beginCol = 1代表第一列</param>
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();
}
}
} /// <summary>
/// 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
/// </summary>
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();
} /// <summary>
/// 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
/// </summary>
/// <param name="fileName">文件名,包括文件路径</param>
public void Save(string fileName)
{
this.fileName = fileName;
Save();
} /// <summary>
/// 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
/// </summary>
/// <param name="fileName">文件名,包括文件路径</param>
/// <param name="encoding">文件编码</param>
public void Save(string fileName,Encoding encoding)
{
this.fileName = fileName;
this.encoding = encoding;
Save();
} /// <summary>
/// 转换成保存行
/// </summary>
/// <param name="colAL">一行</param>
/// <returns></returns>
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;
} /// <summary>
/// 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
/// </summary>
/// <param name="cell">格子内容</param>
/// <returns></returns>
private string ConvertToSaveCell(string cell)
{
cell = cell.Replace("/"","/"/""); return "/"" + cell + "/"";
}
}
}