如何使用C＃将数据插入SQL Sever而不使用数据库向导（visual studio）

Question

I'm having trouble inserting data into my table called "client" in my database called "vet".

I'm trying to do the connection manually as opposed to using the database wizard. I want to do it this way so that i can hide the majority of my code in a separate class.

I have a feeling I have the logic for this all wrong as I'm not making use of a data set, I was hoping someone could point me in the right direction.

This is for a school assignment and not for real world use. I have read a number of similar posts but am still unable to come to a solution.

public void CommitToDatabase()
{
    using (var con = new SqlConnection(CLSDatabaseDetails.GlobalConnectionString))
    {
        DataTable client = new DataTable();
        DataSet ds = new DataSet();
        string commandString = "SELECT * FROM client";
        SqlCommand cmd = new SqlCommand(commandString, con);
        con.Open();
        SqlDataAdapter da = new SqlDataAdapter(cmd);
        da.Fill(client);
        DataRow newClientRow = ds.Tables["client"].NewRow();
        newClientRow["ClientID"] = ClientID;
        newClientRow["FirstName"] = FirstName;
        newClientRow["LastName"] = LastName;
        newClientRow["Phone"] = PhoneNumber;
        newClientRow["CAddress"] = Address;
        newClientRow["Email"] = Email;
        newClientRow["CUsername"] = Username;
        newClientRow["CPassword"] = Password;
        client.Rows.Add(newClientRow);
        da.Update(client);
    }
}

Answer 1

Try something like this:

public void CommitToDatabase()
{
    using (var con = new SqlConnection(CLSDatabaseDetails.GlobalConnectionString))
    {
        DataTable client = new DataTable();
        string commandString = "SELECT * FROM client";
        SqlCommand cmd = new SqlCommand(commandString, con);
        con.Open();
        SqlDataAdapter da = new SqlDataAdapter(cmd);
        da.Fill(client);
        DataRow newClientRow = client.NewRow();
        newClientRow["ClientID"] = ClientID;
        newClientRow["FirstName"] = FirstName;
        newClientRow["LastName"] = LastName;
        newClientRow["Phone"] = PhoneNumber;
        newClientRow["CAddress"] = Address;
        newClientRow["Email"] = Email;
        newClientRow["CUsername"] = Username;
        newClientRow["CPassword"] = Password;
        client.Rows.Add(newClientRow);
        da.Update(client);
    }
}

Answer 2

A DataSet is a collection of DataTable s. In your example, you're only referring to one table. The SqlDataAdapter.Fill method will populate either DataSet or DataTable . You're calling da.Fill(client) which is fine - it will fill the DataTable client . You could also call da.Fill(ds, "client") which will fill the DataSet ds . You can then extract your table via ds.Tables["client"] . Using a DataSet in this example is overkill, but you can show your tutor how a DataSet works.

You're filling the DataTable but then adding the new row with reference to the DataSet. But in your example, the DataSet ds has nothing in it, because you filled the DataTable not the DataSet. Try this:

DataSet ds = new DataSet();
string commandString = "SELECT TOP 0 * FROM client";
SqlCommand cmd = new SqlCommand(commandString, con);
con.Open();
SqlDataAdapter da = new SqlDataAdapter(cmd);
SqlCommandBuilder builder = new SqlCommandBuilder(da);
da.Fill(ds, "client");
DataTable client = ds.Tables["client"];
DataRow newClientRow = client.NewRow();
... ... ... 
client.Rows.Add(newClientRow);
builder.GetInsertCommand();
da.Update(client);

If you only want to insert a row, you don't need to SELECT all the rows. If you SELECT TOP 0 * from client you'll get the column names (which you need) but without the overhead of returning all the rows.

Answer 3

I can't tell what the source of your data is. Anyway, here are two examples of moving data from a CSV file to SQL Server and from a DataGridView to SQL Server.

using Microsoft.VisualBasic;
using System;
using System.Collections;
using System.Collections.Generic;
using System.Data;
using System.Diagnostics;
using System.Data.SqlClient;
using System.IO;
using Microsoft.VisualBasic.FileIO;
using System.Data.Odbc;
using System.Data.OleDb;
using System.Configuration;


public class Form1
{


    private void Button1_Click(System.Object sender, System.EventArgs e)
    {

        dynamic headers = (from header in DataGridView1.Columns.Cast<DataGridViewColumn>()header.HeaderText).ToArray;
        dynamic rows = from row in DataGridView1.Rows.Cast<DataGridViewRow>()where !row.IsNewRowArray.ConvertAll(row.Cells.Cast<DataGridViewCell>.ToArray, c => c.Value != null ? c.Value.ToString : "");
        string str = "";
        using (IO.StreamWriter sw = new IO.StreamWriter("C:\\Users\\Excel\\Desktop\\OrdersTest.csv")) {
            sw.WriteLine(string.Join(",", headers));
            //sw.WriteLine(String.Join(","))
            foreach (void r_loopVariable in rows) {
                r = r_loopVariable;
                sw.WriteLine(string.Join(",", r));
            }
            sw.Close();
        }

    }

    private void Button2_Click(System.Object sender, System.EventArgs e)
    {
        //Dim m_strConnection As String = "server='Server_Name';Initial Catalog='Database_Name';Trusted_Connection=True;"

        //Catch ex As Exception
        //    MessageBox.Show(ex.ToString())
        //End Try

        //Dim objDataset1 As DataSet()
        //Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        //Dim da As OdbcDataAdapter
        System.Windows.Forms.OpenFileDialog OpenFile = new System.Windows.Forms.OpenFileDialog();
        // Does something w/ the OpenFileDialog
        string strFullPath = null;
        string strFileName = null;
        TextBox tbFile = new TextBox();
        // Sets some OpenFileDialog box options
        OpenFile.Filter = "CSV Files (*.csv)|*.csv|All files (*.*)|*.*";
        // Shows only .csv files
        OpenFile.Title = "Browse to file:";
        // Title at the top of the dialog box

        // Makes the open file dialog box show up
        if (OpenFile.ShowDialog() == DialogResult.OK) {
            strFullPath = OpenFile.FileName;
            // Assigns variable
            strFileName = Path.GetFileName(strFullPath);

            // Checks to see if they've picked a file
            if (OpenFile.FileNames.Length > 0) {

                tbFile.Text = strFullPath;
                // Puts the filename in the textbox

                // The connection string for reading into data connection form
                string connStr = null;
                connStr = "Driver={Microsoft Text Driver (*.txt; *.csv)}; Dbq=" + Path.GetDirectoryName(strFullPath) + "; Extensions=csv,txt ";

                // Sets up the data set and gets stuff from .csv file
                OdbcConnection Conn = new OdbcConnection(connStr);
                DataSet ds = default(DataSet);
                OdbcDataAdapter DataAdapter = new OdbcDataAdapter("SELECT * FROM [" + strFileName + "]", Conn);
                ds = new DataSet();

                try {
                    DataAdapter.Fill(ds, strFileName);
                    // Fills data grid..
                    DataGridView1.DataSource = ds.Tables(strFileName);
                    // ..according to data source

                    // Catch and display database errors
                } catch (OdbcException ex) {
                    OdbcError odbcError = default(OdbcError);
                    foreach ( odbcError in ex.Errors) {
                        MessageBox.Show(ex.Message);
                    }
                }

                // Cleanup
                OpenFile.Dispose();
                Conn.Dispose();
                DataAdapter.Dispose();
                ds.Dispose();

            }
        }

    }

    private void Button3_Click(System.Object sender, System.EventArgs e)
    {
        SqlConnection cnn = default(SqlConnection);
        string connectionString = null;
        string sql = null;

        connectionString = "data source='Server_Name';" + "initial catalog='Database_Name';Trusted_Connection=True";
        cnn = new SqlConnection(connectionString);
        cnn.Open();
        sql = "SELECT * FROM [Order Details]";
        SqlDataAdapter dscmd = new SqlDataAdapter(sql, cnn);
        DataSet ds = new DataSet();
        dscmd.Fill(ds);
        DataGridView1.DataSource = ds.Tables(0);

        cnn.Close();

    }


    private void ProductsDataGridView_CellFormatting(object sender, System.Windows.Forms.DataGridViewCellFormattingEventArgs e)
    {
        if (e.ColumnIndex == DataGridView1.Columns(3).Index && e.Value != null) {
            //
            if (Convert.ToInt32(e.Value) < 10) {
                e.CellStyle.BackColor = Color.OrangeRed;
                e.CellStyle.ForeColor = Color.LightGoldenrodYellow;
            }
            //
        }
        //
    }

    //Private Sub ProductsDataGridView_CellFormatting(ByVal sender As Object, _
    //    ByVal e As System.Windows.Forms.DataGridViewCellFormattingEventArgs) _
    //        Handles DataGridView1.CellFormatting
    //    '
    //    If e.ColumnIndex = DataGridView1.Columns("DataGridViewTextBoxColumn8").Index _
    //        AndAlso e.Value IsNot Nothing Then
    //        '
    //        If CInt(e.Value) < 5 Then
    //            e.CellStyle.BackColor = Color.OrangeRed
    //            e.CellStyle.ForeColor = Color.LightGoldenrodYellow
    //        End If
    //        '
    //    End If
    //    '
    //End Sub


    //If e.ColumnIndex = ProductsDataGridView.Columns(4).Index _
    //AndAlso e.Value IsNot Nothing Then
    //'
    //    If CInt(e.Value) = 0 Then
    //        e.CellStyle.BackColor = Color.OrangeRed
    //        e.CellStyle.ForeColor = Color.LightGoldenrodYellow
    //    End If
    //End If

    // ''To (you need to change the column name)
    //    If e.ColumnIndex = ProductsDataGridView.Columns("YourColumnName").Index _
    //    AndAlso e.Value IsNot Nothing Then
    //'
    //    If CInt(e.Value) = 0 Then
    //        e.CellStyle.BackColor = Color.OrangeRed
    //        e.CellStyle.ForeColor = Color.LightGoldenrodYellow
    //    End If
    //End If


    private void Button4_Click(System.Object sender, System.EventArgs e)
    {
        DataTable tblReadCSV = new DataTable();

        tblReadCSV.Columns.Add("FName");
        tblReadCSV.Columns.Add("LName");
        tblReadCSV.Columns.Add("Department");

        TextFieldParser csvParser = new TextFieldParser("C:\\Users\\Excel\\Desktop\\Employee.txt");

        csvParser.Delimiters = new string[] { "," };
        csvParser.TrimWhiteSpace = true;
        csvParser.ReadLine();

        while (!(csvParser.EndOfData == true)) {
            tblReadCSV.Rows.Add(csvParser.ReadFields());
        }

        SqlConnection con = new SqlConnection("Server='Server_Name';Database='Database_Name';Trusted_Connection=True;");
        string strSql = "Insert into Employee(FName,LName,Department) values(@Fname,@Lname,@Department)";
        //Dim con As New SqlConnection(strCon)
        SqlCommand cmd = new SqlCommand();
        cmd.CommandType = CommandType.Text;
        cmd.CommandText = strSql;
        cmd.Connection = con;
        cmd.Parameters.Add("@Fname", SqlDbType.VarChar, 50, "FName");
        cmd.Parameters.Add("@Lname", SqlDbType.VarChar, 50, "LName");
        cmd.Parameters.Add("@Department", SqlDbType.VarChar, 50, "Department");

        SqlDataAdapter dAdapter = new SqlDataAdapter();
        dAdapter.InsertCommand = cmd;
        int result = dAdapter.Update(tblReadCSV);

    }


    private void Button5_Click(System.Object sender, System.EventArgs e)
    {
        string SQLConnectionString = "Data Source=Excel-PC\\SQLEXPRESS;" + "Initial Catalog=Northwind;" + "Trusted_Connection=True";

        // Open a connection to the AdventureWorks database.
        using (SqlConnection SourceConnection = new SqlConnection(SQLConnectionString)) {
            SourceConnection.Open();

            // Perform an initial count on the destination table.
            SqlCommand CommandRowCount = new SqlCommand("SELECT COUNT(*) FROM dbo.Orders;", SourceConnection);
            long CountStart = System.Convert.ToInt32(CommandRowCount.ExecuteScalar());
            Console.WriteLine("Starting row count = {0}", CountStart);

            // Get data from the source table as a AccessDataReader.
            //Dim ConnectionString As String = "Provider=Microsoft.Jet.OLEDB.4.0;" & _
            //    "Data Source=" & "C:\Users\Excel\Desktop\OrdersTest.txt" & ";" & _
            //    "Extended Properties=" & "text;HDR=Yes;FMT=Delimited"","";"

            string ConnectionString = "Provider=Microsoft.Jet.OLEDB.4.0;" + "Data Source=" + "C:\\Users\\Excel\\Desktop\\" + ";" + "Extended Properties=\"Text;HDR=No\"";

            System.Data.OleDb.OleDbConnection TextConnection = new System.Data.OleDb.OleDbConnection(ConnectionString);

            OleDbCommand TextCommand = new OleDbCommand("SELECT * FROM OrdersTest#csv", TextConnection);
            TextConnection.Open();
            OleDbDataReader TextDataReader = TextCommand.ExecuteReader(CommandBehavior.SequentialAccess);

            // Open the destination connection.              
            using (SqlConnection DestinationConnection = new SqlConnection(SQLConnectionString)) {
                DestinationConnection.Open();

                // Set up the bulk copy object. 
                // The column positions in the source data reader 
                // match the column positions in the destination table, 
                // so there is no need to map columns.
                using (SqlBulkCopy BulkCopy = new SqlBulkCopy(DestinationConnection)) {
                    BulkCopy.DestinationTableName = "dbo.Orders";

                    try {
                        // Write from the source to the destination.
                        BulkCopy.WriteToServer(TextDataReader);

                    } catch (Exception ex) {
                        Console.WriteLine(ex.Message);

                    } finally {
                        // Close the AccessDataReader. The SqlBulkCopy
                        // object is automatically closed at the end
                        // of the Using block.
                        TextDataReader.Close();
                    }
                }

                // Perform a final count on the destination table
                // to see how many rows were added.
                long CountEnd = System.Convert.ToInt32(CommandRowCount.ExecuteScalar());
                //Console.WriteLine("Ending row count = {0}", CountEnd)
                //Console.WriteLine("{0} rows were added.", CountEnd - CountStart)
            }
        }


        //Dim FILE_NAME As String = "C:\Users\Excel\Desktop\OrdersTest.csv"
        //Dim TextLine As String

        //If System.IO.File.Exists(FILE_NAME) = True Then
        //    Dim objReader As New System.IO.StreamReader(FILE_NAME)
        //    Do While objReader.Peek() <> -1
        //        TextLine = TextLine & objReader.ReadLine() & vbNewLine
        //    Loop
        //Else
        //    MsgBox("File Does Not Exist")
        //End If

        //Dim cn As New SqlConnection("Data Source=Excel-PC\SQLEXPRESS;Initial Catalog=Northwind;Trusted_Connection=True;")
        //Dim cmd As New SqlCommand

        //cmd.Connection = cn

        //cmd.Connection.Close()
        //cmd.Connection.Open()

        //cmd.CommandText = "INSERT INTO Orders (OrderID,CustomerID,EmployeeID,OrderDate,RequiredDate,ShippedDate,ShipVia,Freight,ShipName,ShipAddress,ShipCity,ShipRegion,ShipPostalCode,ShipCountry) values & OrdersTest.csv"
        //cmd.ExecuteNonQuery()
        //cmd.Connection.Close()

    }


    private void Button6_Click(System.Object sender, System.EventArgs e)
    {
        // Define the Column Definition                             
        DataTable dt = new DataTable();
        dt.Columns.Add("OrderID", typeof(int));
        dt.Columns.Add("CustomerID", typeof(string));
        dt.Columns.Add("EmployeeID", typeof(int));
        dt.Columns.Add("OrderDate", typeof(System.DateTime));
        dt.Columns.Add("RequiredDate", typeof(System.DateTime));
        dt.Columns.Add("ShippedDate", typeof(System.DateTime));
        dt.Columns.Add("ShipVia", typeof(int));
        dt.Columns.Add("Freight", typeof(decimal));
        dt.Columns.Add("ShipName", typeof(string));
        dt.Columns.Add("ShipAddress", typeof(string));
        dt.Columns.Add("ShipCity", typeof(string));
        dt.Columns.Add("ShipRegion", typeof(string));
        dt.Columns.Add("ShipPostalCode", typeof(string));
        dt.Columns.Add("ShipCountry", typeof(string));
        using (cn == new SqlConnection("Server='Server_Name';Database='Database_Name';Trusted_Connection=True;")) {
            cn.Open();
            Microsoft.VisualBasic.FileIO.TextFieldParser reader = default(Microsoft.VisualBasic.FileIO.TextFieldParser);
            string[] currentRow = null;
            DataRow dr = default(DataRow);
            string sqlColumnDataType = null;
            reader = My.Computer.FileSystem.OpenTextFieldParser("C:\\Users\\Excel\\Desktop\\OrdersTest.csv");
            reader.TextFieldType = Microsoft.VisualBasic.FileIO.FieldType.Delimited;
            reader.Delimiters = new string[] { "," };
            while (!reader.EndOfData) {
                try {
                    currentRow = reader.ReadFields();
                    dr = dt.NewRow();
                    for (currColumn = 0; currColumn <= dt.Columns.Count - 1; currColumn++) {
                        sqlColumnDataType = dt.Columns(currColumn).DataType.Name;
                        switch (sqlColumnDataType) {
                            case "String":
                                if (string.IsNullOrEmpty(currentRow(currColumn))) {
                                    dr.Item(currColumn) = "";
                                } else {
                                    dr.Item(currColumn) = Convert.ToString(currentRow(currColumn));
                                }
                                break;
                            case "Decimal":
                                if (string.IsNullOrEmpty(currentRow(currColumn))) {
                                    dr.Item(currColumn) = 0;
                                } else {
                                    dr.Item(currColumn) = Convert.ToDecimal(currentRow(currColumn));
                                }
                                break;
                            case "DateTime":
                                if (string.IsNullOrEmpty(currentRow(currColumn))) {
                                    dr.Item(currColumn) = "";
                                } else {
                                    dr.Item(currColumn) = Convert.ToDateTime(currentRow(currColumn));
                                }
                                break;
                        }
                    }
                    dt.Rows.Add(dr);
                } catch (Microsoft.VisualBasic.FileIO.MalformedLineException ex) {
                    Interaction.MsgBox("Line " + ex.Message + "is not valid." + Constants.vbCrLf + "Terminating Read Operation.");
                    reader.Close();
                    reader.Dispose();
                    //Return False
                } finally {
                    dr = null;
                }
            }
            using (SqlBulkCopy copy = new SqlBulkCopy(cn)) {
                copy.DestinationTableName = "[dbo].[Orders]";
                copy.WriteToServer(dt);
            }
        }

    }


    public static bool GetCsvData(string CSVFileName, ref DataTable CSVTable)
    {
        Microsoft.VisualBasic.FileIO.TextFieldParser reader = default(Microsoft.VisualBasic.FileIO.TextFieldParser);
        string[] currentRow = null;
        DataRow dr = default(DataRow);
        string sqlColumnDataType = null;
        reader = My.Computer.FileSystem.OpenTextFieldParser(CSVFileName);
        reader.TextFieldType = Microsoft.VisualBasic.FileIO.FieldType.Delimited;
        reader.Delimiters = new string[] { "," };
        while (!reader.EndOfData) {
            try {
                currentRow = reader.ReadFields();
                dr = CSVTable.NewRow();
                for (currColumn = 0; currColumn <= CSVTable.Columns.Count - 1; currColumn++) {
                    sqlColumnDataType = CSVTable.Columns(currColumn).DataType.Name;
                    switch (sqlColumnDataType) {
                        case "String":
                            if (string.IsNullOrEmpty(currentRow(currColumn))) {
                                dr.Item(currColumn) = "";
                            } else {
                                dr.Item(currColumn) = Convert.ToString(currentRow(currColumn));
                            }
                            break;
                        case "Decimal":
                            if (string.IsNullOrEmpty(currentRow(currColumn))) {
                                dr.Item(currColumn) = 0;
                            } else {
                                dr.Item(currColumn) = Convert.ToDecimal(currentRow(currColumn));
                            }
                            break;
                        case "DateTime":
                            if (string.IsNullOrEmpty(currentRow(currColumn))) {
                                dr.Item(currColumn) = "";
                            } else {
                                dr.Item(currColumn) = Convert.ToDateTime(currentRow(currColumn));
                            }
                            break;
                    }
                }
                CSVTable.Rows.Add(dr);
            } catch (Microsoft.VisualBasic.FileIO.MalformedLineException ex) {
                Interaction.MsgBox("Line " + ex.Message + "is not valid." + Constants.vbCrLf + "Terminating Read Operation.");
                reader.Close();
                reader.Dispose();
                return false;
            } finally {
                dr = null;
            }
        }
        reader.Close();
        reader.Dispose();
        return true;
    }
}

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