在 Android 如何使用光标将新行附加到 .CSV 文件

Question

我从事这项工作已经有一段时间了，我最多只能将整个查询从数据库写入一长行的 .CSV 文件。

当我将 writeNext(string[]) 与下面的代码一起使用时，.csv 被写在一长行上。

//Export the orders in the database to a CSV file.  Can be transferred from device either by USB or bluetooth
public void exportOrders(View view)
{
    try
    {
        CSVWriter writer;
        writer = new CSVWriter(new FileWriter("/sdcard/orders.csv"), ',');
        writer.writeNext(cursor.getColumnNames()); //Write the column headings first before the looping starts
        //Loop through all results (use row count of table)
        for(cursor.moveToFirst(); !cursor.isAfterLast(); cursor.moveToNext())
        {
            String[] entries = (cursor.getString(0)+ "," +cursor.getString(1)+ "," +cursor.getString(2)+ "," +cursor.getString(3)
                    + "," +cursor.getString(4)).split(","); //Split the string by the delimiter
            writer.writeNext(entries); //Write current row of DB to file
            writer.flush(); //Flush the stream
        }
        Toast.makeText(this, "Orders exported to .CSV successfully!", Toast.LENGTH_SHORT).show();
        writer.close();
    }
    catch (Exception erMsg)
    {
        Toast.makeText(this, erMsg.toString(), Toast.LENGTH_LONG).show();
        erMsg.printStackTrace();
    }
}

根据我的阅读，这似乎是实现它的方法，但我看不出如何从该代码生成新行？有没有办法在新行中使用 Cursor，或者使用 ResultSet 和 writeAll(result) 是标准的吗？

Answer 1

这样做的解决方案是使用正确的参数声明 CSVWriter。这是新的构造函数：

writer = new CSVWriter(new FileWriter("/sdcard/orders.csv"), ',',  CSVWriter.NO_QUOTE_CHARACTER, CSVWriter.DEFAULT_ESCAPE_CHARACTER, "\r\n");

这将允许为每一行创建一个新行。为确保这有效，请使用 "\r\n" 而不是 "\n"" 因为有些编辑不认识 "\n".

在 Android 如何使用光标将新行附加到 .CSV 文件

In Android how to append a new line to .CSV file with a Cursor

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