一、CSV文件规则
1 开头是不留空，以行为单位。
2 可含或不含列名，含列名则居文件第一行。
3 一行数据不跨行，无空行。
4 以半角逗号（即,）作分隔符，列为空也要表达其存在。
5 列内容如存在半角逗号（即,）则用半角引号（即‘,‘）将该字段值包含起来。
6 列内容如存在半角引号（即"）则应替换成半角双引号（""）转义，并用半角引号（即""）将该字段值包含起来。
7 文件读写时引号，逗号操作规则互逆。
8 内码格式不限，可为 ASCII、Unicode 或者其他。
9 不支持特殊字符
二、C#读取csv文件的方法
C# 代码 复制
//读CSV文件类,读取指定的CSV文件，可以导出DataTable
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)
{
//System.Diagnostics.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;
}
}
