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C# 如何使用for循环一次读取一个csv?_C#_Asp.net - Fatal编程技术网

C# 如何使用for循环一次读取一个csv?

C# 如何使用for循环一次读取一个csv?,c#,asp.net,C#,Asp.net,字符串fromdatetime类似于12162013_0730.csv,字符串todatetime类似于12162013_0930.csv…如何使用for循环读取fromdatetime到DateTime之间的文件。。。阅读12162013_0730.csv、12162013_0830.csv、12162013_0930.csv,一次一个文件?如果您当前的代码工作正常,则可以执行以下操作 string todate = txtToDate1.Text; string fromtime = Dro

字符串fromdatetime类似于12162013_0730.csv,字符串todatetime类似于12162013_0930.csv…如何使用for循环读取fromdatetime到DateTime之间的文件。。。阅读12162013_0730.csv、12162013_0830.csv、12162013_0930.csv,一次一个文件?

如果您当前的代码工作正常,则可以执行以下操作

string todate = txtToDate1.Text;
string fromtime = DropDownList2.SelectedItem.Text;
string totime = DropDownList3.SelectedItem.Text;

string fromdatetime = fromdate + "_" + fromtime;
string todatetime = todate + "_" + totime;


con.ConnectionString = constr;

//create instance for command object 
OleDbCommand cmd = new OleDbCommand();


cmd.Connection = con;   
// set your file name in the below query
cmd.CommandText = "select * from " + fromdatetime + ".csv ";



//Open Oledb Connection to read CSV file 
con.Open(); 

//Create one datatable to store data from CSV file
DataTable dt = new DataTable();

// Load Data into the datatable 
dt.Load(cmd.ExecuteReader());
DateTime start=DateTime.ParseExact(“09162014_0830”,“MMddyyyy_hhmm”,CultureInfo.InvariantCulture);
DateTime end=DateTime.ParseExact(“11162014_0830”,“MMddyyyy_hhmm”,CultureInfo.InvariantCulture);
con.open()
var dt=新数据表();

while(开始)你遇到什么问题?我需要一个for循环,比如for(从datetime到datetime+1hour){cmd.commandtext(从0730到0930获取csv文件)}我需要一个接一个地读取csv文件073008300930和您当前的代码,从一个.csv文件读取有效吗?是的,它只对单个文件有效..但我使用“选择计数…”要计算通过值…如何实际显示一个表中的不同列..比如在09162014上我得到了50通过,在10162014上我得到了60通过…@user3145376我不确定你的意思,最好问一个新的更详细的问题。
DateTime start = DateTime.ParseExact("09162014_0830", "MMddyyyy_hhmm", CultureInfo.InvariantCulture);
DateTime end = DateTime.ParseExact("11162014_0830", "MMddyyyy_hhmm", CultureInfo.InvariantCulture);

               con.open()
               var dt = new DataTable();
               while (start <= end)
               {
                   string csvname = start.ToString("MMddyyyy_hhmm")+".csv";
                   cmd.CommandText = "select * from " + csvname ;
                   var tempdt = new DataTable();
                   tempdt.Load(cmd.ExecuteReader());
                   dt.Merge(tempdt);
                   start = start.AddHours(1d);
               }
               con.close()