Question

我正在尝试读取.csv文件中的数据并将数据插入到mysql数据库中。 .csv文件和数据库有4列。

我可以将数据插入数据库。连接工作正常，但我无法从数据库中右侧字段的.csv文件中获取字段。

那么如何使用我正在使用的方法从数据库中相同字段的.csv文件中获取字段？

我的代码与此类似：

Using MyReader As New Microsoft.VisualBasic.FileIO.TextFieldParser("C:\ParserText.csv")
MyReader.TextFieldType = Microsoft.VisualBasic.FileIO.FieldType.Delimited
MyReader.Delimiters = New String() {","}
Dim currentRow As String()
While Not MyReader.EndOfData
    Try
        currentRow = MyReader.ReadFields()
        For Each currentField As String In currentRow

            /*Use sql to insert data to database here*/

            cmd.commandText = "INSERT INTO mydatabase(column1, column2, column3, column4) VALUES(??, ??, ??, ??)"
            cmd.ExecuteNonQuery()

        Next 
    Catch ex As Microsoft.VisualBasic.FileIO.MalformedLineException
        MsgBox("Line " & ex.Message & " is invalid.  Skipping")
    End Try 
    End While 
End Using

Answer 1

试试这段代码

    Using MyReader As New Microsoft.VisualBasic.FileIO.TextFieldParser("C:\ParserText.csv")
   dim table as new datatable 
MyReader.TextFieldType = Microsoft.VisualBasic.FileIO.FieldType.Delimited
    MyReader.Delimiters = New String() {","}
    myreader.Readline()

Do Until myreader.EndOfData = True
     table.Rows.Add(myreader.ReadFields())
Loop
                       'Use sql to insert data to database here
    for intconut=0 to table.rows.count-1
                cmd.commandText = "INSERT INTO mydatabase(column1, column2, column3, column4) VALUES('" &table.rows(intcount).item(0) & "','" & table.rows(intcount).item(1) & "','" & table.rows(intcount).item(2) & "', '" & table.rows(intcount).item(3)) & "')"
                cmd.ExecuteNonQuery()

     Next 
        Catch ex As Microsoft.VisualBasic.FileIO.MalformedLineException
            MsgBox("Line " & ex.Message & " is invalid.  Skipping")
        End Try 
        End While 
    End Using

这可能会有所帮助。

Answer 2

不使用sql parameterised queries。您可以更改while子句的内部以匹配以下内容：

While Not MyReader.EndOfData
    Try
        currentRow = MyReader.ReadFields()

        cmd.commandText = string.Format("INSERT INTO mydatabase(column1, column2, column3, column4) VALUES (""{0}"", ""{1}"", ""{2}"", ""{3}"")", currentRow[0], currentRow[1], currentRow[2], currentRow[3])

        cmd.ExecuteNonQuery()

        Catch ex As Microsoft.VisualBasic.FileIO.MalformedLineException
        MsgBox("Line " & ex.Message & " is invalid.  Skipping")
    End Try 
End While

了解此代码的工作原理后，您应该将其替换为parameterised query。

TextFieldParser读取文件并插入数据库

2 个答案: