1.把cvs读取到dt中
/// <summary>
/// 把csv读到dt中
/// </summary>
/// <param name="file">csv文件路径</param>
/// <returns>dt</returns>
public static DataTable ReadDataFromCsv(string file)
{
DataTable dt = null;
if (File.Exists(file))
{
#region 如果文件存在
dt = new DataTable();
FileStream fs = new FileStream(file, FileMode.OpenOrCreate, FileAccess.Read);
StreamReader sr = new StreamReader(fs,Encoding.Default);
string head = sr.ReadLine();
string[] headNames = head.Split(',');
for (int i = 0; i < headNames.Length; i++)
{
dt.Columns.Add(headNames[i], typeof(string));
}
while (!sr.EndOfStream)
{
#region ==循环读取文件==
string lineStr = sr.ReadLine();
if (lineStr == null || lineStr.Length == 0)
continue;
string[] values = lineStr.Split(',');
#region ==添加行数据==
DataRow dr = dt.NewRow();
for (int i = 0; i < values.Length; i++)
{
dr[i] = values[i];
}
dt.Rows.Add(dr);
#endregion
#endregion
}
fs.Close();
sr.Close();
#endregion
}
return dt;
}
2.从dt中写入csv
static public void toCsv(DataTable dt, string fullPath)
{
FileInfo fi = new FileInfo(fullPath);
if (!fi.Directory.Exists)
{
fi.Directory.Create();
}
FileStream fs = new FileStream(fullPath, FileMode.Create, FileAccess.Write);
StreamWriter sw = new StreamWriter(fs, Encoding.UTF8);
string data = "";
//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);
//写出各行数据
for (int i = 0; i < dt.Rows.Count; i++)
{
data = "";
for (int j = 0; j < dt.Columns.Count; j++)
{
string str = dt.Rows[i][j].ToString();
str = str.Replace("\"", "\"\"");//替换英文冒号 英文冒号需要换成两个冒号
if (str.Contains(',') || str.Contains('"')
|| str.Contains('\r') || str.Contains('\n')) //含逗号 冒号 换行符的需要放到引号中
{
str = string.Format("\"{0}\"", str);
}
data += str;
if (j < dt.Columns.Count - 1)
{
data += ",";
}
}
sw.WriteLine(data);
}
sw.Close();
fs.Close();
}