Question

如何在指定列的CSV文件中写入值

假设我想写第4列，假设第一行的前三列已经有值。

我无法做到

下面是我的代码

1064 you have an error in your sql syntax near 'MAX(IF(purchasables.sku = '999992', lineitems.qty, NULL)) AS '999992',MAX(IF(pur' at line 1

Answer 1

这是一个简单的CSV编辑类，基于1的索引。

public final class CSV {
    private final List<String[]> cells;

    public CSV(File file) throws IOException {
        cells = new ArrayList<>();
        try (Scanner scan = new Scanner(file)) {
            while (scan.hasNextLine()) {
                String line = scan.nextLine();
                cells.add(line.split(","));
            }
        }
    }

    public String get(int row, int col) {
        String columns = cells.get(row - 1);
        return columns[col - 1];
    }

    public CSV set(int row, int col, String value) {
        String columns = cells.get(row - 1);
        columns[col - 1] = value;
        return this;
    }

    public void save(File file) throws IOException {
        try (PrintWriter out = new PrintWriter(file)) {
            for (String[] row : cells) {
                for (String cell : row) {
                    if (cell != row[0]) {
                        out.print(",");
                    }
                    out.print(cell);
                }
                out.printLn();
            }
        }
    }
}

现在你可以做到

File file = new 
    File("C:\\docs\\test\\COLD_SOAK_1_engine_20171002014945.csv");
new CSV(file).set(1, 4, "new value").save(file);

但这对于在值中引用逗号的CSV文件不起作用。

使用java写入CSV文件中的指定列

1 个答案: