1、引入以下命名空间
using System;
using System.Data;
using System.IO;
2、将DataTable写入CSV文件
/// <summary>
/// 写入CSV文件
/// </summary>
/// <param name="dt">DataTable</param>
/// <param name="fullFileName">文件全名</param>
/// <returns>是否写入成功</returns>
public static bool SaveCSV(DataTable dt, string fullFileName)
{
bool r = false;
FileStream fs = new FileStream(fullFileName, System.IO.FileMode.Create, System.IO.FileAccess.Write);
StreamWriter sw = new StreamWriter(fs, System.Text.Encoding.Default);
string data = string.Empty;
//写出列名称
for (int i = 0; i < dt.Columns.Count; i++)
{
data += dt.Columns[i].ColumnName.ToString();
if (i < dt.Columns.Count - 1)
{
data += ",";
}
}
sw.WriteLine(data);
//写入各行数据
for (int i = 0; i < dt.Rows.Count; i++)
{
data = string.Empty;
for (int j = 0; j < dt.Columns.Count; j++)
{
data += dt.Rows[i][j].ToString();
if (j < dt.Columns.Count - 1)
{
data += ",";
}
}
sw.WriteLine(data);
}
sw.Close();
fs.Close();
r = true;
return r;
}
3、打开CSV文件,返回DataTable
/// <summary>
/// 打开CSV 文件
/// </summary>
/// <param name="fullFileName">文件全名</param>
/// <param name="firstRow">开始行</param>
/// <param name="firstColumn">开始列</param>
/// <param name="getRows">获取多少行</param>
/// <param name="getColumns">获取多少列</param>
/// <param name="haveTitleRow">是有标题行</param>
/// <returns>DataTable</returns>
public static DataTable OpenCSV(string fullFileName, int firstRow = 0, int firstColumn = 0, int getRows = 0, int getColumns = 0, bool haveTitleRow = false)
{
try
{
DataTable dt = new DataTable();
FileStream fs = new FileStream(fullFileName, System.IO.FileMode.Open, System.IO.FileAccess.Read);
StreamReader sr = new StreamReader(fs, System.Text.Encoding.Default);
//记录每次读取的一行记录
string strLine = string.Empty;
//记录每行记录中的各字段内容
string[] aryLine;
//标示列数
int columnCount = 0;
//是否已建立了表的字段
bool bCreateTableColumns = false;
//第几行
int iRow = 1;
//去除无用行
if (firstRow > 0)
{
for (int i = 1; i < firstRow; i++)
{
sr.ReadLine();
}
}
// { ",", ".", "!", "?", ";", ":", " " };
string[] separators = { "," };
//逐行读取CSV中的数据
while ((strLine = sr.ReadLine()) != null)
{
strLine = strLine.Trim();
while (strLine.Contains(",,"))
{
strLine = strLine.Replace(",,", ",0,");
}
aryLine = strLine.Split(separators, System.StringSplitOptions.RemoveEmptyEntries);
if (bCreateTableColumns == false)
{
bCreateTableColumns = true;
columnCount = aryLine.Length;
//创建列
for (int i = firstColumn; i < (getColumns == 0 ? columnCount : firstColumn + getColumns); i++)
{
DataColumn dc
= new DataColumn(haveTitleRow == true ? aryLine[i] : "COL" + i.ToString());
dt.Columns.Add(dc);
}
bCreateTableColumns = true;
if (haveTitleRow == true)
{
continue;
}
}
DataRow dr = dt.NewRow();
//for (int j = firstColumn; j < (getColumns == 0 ? columnCount : firstColumn + getColumns); j++)
for (int j = firstColumn; j < aryLine.Length; j++)
{
if (j < dt.Columns.Count)
{
dr[j - firstColumn] = aryLine[j];
}
}
dt.Rows.Add(dr);
iRow = iRow + 1;
if (getRows > 0)
{
if (iRow > getRows)
{
break;
}
}
}
sr.Close();
fs.Close();
return dt;
}
catch (Exception ex)
{
throw ex;
}
}