我正在读取一个CSV文件，但它只使得SQL表有2列（ID和test）`但它不会用CSV文件中的值填充这些列。这是我得到的代码：
public void GetDataTabletFromCSVFile2(string csv_file_path, string tablenaam)
{
string cn = ConfigurationManager.ConnectionStrings["Scratchpad"].ConnectionString;
using (SqlConnection dbConnection = new SqlConnection(cn))
{
using (SqlCommand cmd = new SqlCommand())
{
cmd.Connection = dbConnection;
cmd.CommandType = CommandType.Text;
cmd.CommandText = $@"CREATE TABLE test (
[ID] INT IDENTITY (1, 1) NOT NULL,
[testingcolumn] VARCHAR (1023) NULL,
CONSTRAINT [PK_{test}] PRIMARY KEY CLUSTERED ([ID] ASC)
)";
try
{
dbConnection.Open();
cmd.ExecuteNonQuery();
}
catch (SqlException e)
{
MessageBox.Show(e.Message.ToString(), "Error Message");
}
finally
{
dbConnection.Close();
}
}
}
string line;
System.Data.DataTable csvData = new System.Data.DataTable();
// Read the file and display it line by line.
System.IO.StreamReader file = new System.IO.StreamReader(csv_file_path);
while ((line = file.ReadLine()) != null)
{
DataRow newRow = csvData.NewRow();
csvData.Rows.Add(newRow);
}
file.Close();
InsertDataIntoSQLServerUsingSQLBulkCopy2(csvData, tablenaam);
}
static void InsertDataIntoSQLServerUsingSQLBulkCopy2(System.Data.DataTable csvFileData, string Tablename)
{
string cn = ConfigurationManager.ConnectionStrings["Scratchpad"].ConnectionString;
using (SqlConnection dbConnection = new SqlConnection(cn))
{
dbConnection.Open();
string sqlTrunc = "TRUNCATE TABLE " + Tablename;
SqlCommand cmd = new SqlCommand(sqlTrunc, dbConnection);
cmd.ExecuteNonQuery();
using (SqlBulkCopy s = new SqlBulkCopy(dbConnection))
{
s.ColumnMappings.Clear();
s.DestinationTableName = Tablename;
foreach (var column in csvFileData.Columns)
s.ColumnMappings.Add(column.ToString(), column.ToString());
s.WriteToServer(csvFileData);
dbConnection.Close();
}
}
}
我的SQL表现在看起来像这样：
------------
| ID | test|
------------
|null|null |
------------
虽然看起来应该是这样的：
-------------
| ID | test |
-------------
|1 |value1|
-------------
|2 |value2|
-------------
|3 |value3|
-------------
string line;
System.Data.DataTable csvData = new System.Data.DataTable();
// Read the file and display it line by line.
System.IO.StreamReader file = new System.IO.StreamReader(csv_file_path);
int i = 0;
DataColumn datecolumn = new DataColumn("ID");
datecolumn.AllowDBNull = true;
csvData.Columns.Add(datecolumn);
DataColumn datecolumn2 = new DataColumn("RunTimeGroupCheck");
datecolumn.AllowDBNull = true;
csvData.Columns.Add(datecolumn2);
while ((line = file.ReadLine()) != null)
{
var id = (i++); //Code this method
var test = (line); //Code this method
csvData.Rows.Add(id, test);
}
file.Close();
InsertDataIntoSQLServerUsingSQLBulkCopy2(csvData, tablenaam);
答案 0 :(得分：1)
在阅读CSV时，您没有对读取的数据做任何事情，因此您的DataTable实际上是空的：
// Read the file and display it line by line.
System.IO.StreamReader file = new System.IO.StreamReader(csv_file_path);
while ((line = file.ReadLine()) != null)
{
DataRow newRow = csvData.NewRow();
// HERE: YOU ARE MISSING PARSING line INTO newRow
csvData.Rows.Add(newRow);
}
答案 1 :(得分：1)
您忘记填充要添加的数据行，您正在正确地创建数据行DataRow newRow = csvData.NewRow();，但您必须填写您在线的信息。
while ((line = file.ReadLine()) != null)
{
DataRow newRow = csvData.NewRow();
//DataRow is empty
csvData.Rows.Add(newRow);
}
while ((line = file.ReadLine()) != null)
{
var id = extractIdFromLine(line); //Code this method
var test= extractTestFromLine(line); //Code this method
csvData.Rows.Add(id, test);
}
选中此oficial post
答案 2 :(得分：1)
您需要正确的数据类型和正确插入。
public void GetDataTabletFromCSVFile2(string csv_file_path, string tablenaam)
{
string cn = ConfigurationManager.ConnectionStrings["Scratchpad"].ConnectionString;
using (SqlConnection dbConnection = new SqlConnection(cn))
{
using (SqlCommand cmd = new SqlCommand())
{
cmd.Connection = dbConnection;
cmd.CommandType = CommandType.Text;
// check if You really want test for table name, not tablenaam
// mind that the column name is same as the DataTable's column name!!!!
cmd.CommandText = $@"CREATE TABLE test (
[ID] INT IDENTITY (1, 1) NOT NULL,
[RunTimeGroupCheck] VARCHAR (1023) NULL,
CONSTRAINT [PK_Test] PRIMARY KEY CLUSTERED ([ID] ASC)
)";
try
{
dbConnection.Open();
cmd.ExecuteNonQuery();
}
catch (SqlException e)
{
MessageBox.Show(e.Message.ToString(), "Error Message");
}
finally
{
dbConnection.Close();
}
}
}
string line;
System.Data.DataTable csvData = new System.Data.DataTable();
DataColumn firstColumn = new DataColumn("ID", typeof(int));
firstColumn.AutoIncrement = true; // This is the thing that enables You to leave the ID column. It will autoincrement.
firstColumn.AutoIncrementSeed = 1;
firstColumn.AutoIncrementStep = 1;
csvData.Columns.Add(firstColumn);
csvData.Columns.Add(new DataColumn("RunTimeGroupCheck", typeof(string)));
// Read the file and display it line by line.
System.IO.StreamReader file = new System.IO.StreamReader(csv_file_path);
while ((line = file.ReadLine()) != null)
{
DataRow newRow = csvData.NewRow();
// missing filling of data. You need the line to be put somewhere.
// also mind, that the newRow["ID"] is not set to anything.
newRow["RunTimeGroupCheck"] = line;
csvData.Rows.Add(newRow);
}
file.Close();
InsertDataIntoSQLServerUsingSQLBulkCopy2(csvData, tablenaam);
}
static void InsertDataIntoSQLServerUsingSQLBulkCopy2(System.Data.DataTable csvFileData, string Tablename)
{
string cn = ConfigurationManager.ConnectionStrings["Scratchpad"].ConnectionString;
using (SqlConnection dbConnection = new SqlConnection(cn))
{
dbConnection.Open();
string sqlTrunc = "TRUNCATE TABLE " + Tablename;
SqlCommand cmd = new SqlCommand(sqlTrunc, dbConnection);
cmd.ExecuteNonQuery();
using (SqlBulkCopy s = new SqlBulkCopy(dbConnection))
{
s.ColumnMappings.Clear();
s.DestinationTableName = Tablename;
foreach (var column in csvFileData.Columns)
s.ColumnMappings.Add(column.ToString(), column.ToString());
s.WriteToServer(csvFileData);
dbConnection.Close();
}
}
}