中文
devexamples

Write CSV Rows From Dictionaries

Write dictionaries to CSV with a declared header order, ensuring every row has the same columns even when fields are missing.

PythonData Integrity

Code

snippet
import csv
import io
from typing import Dict, Iterable, List


def to_csv(rows: Iterable[Dict[str, object]], columns: List[str]) -> str:
    buffer = io.StringIO()
    writer = csv.DictWriter(buffer, fieldnames=columns, extrasaction="ignore")
    writer.writeheader()
    for row in rows:
        writer.writerow({column: row.get(column, "") for column in columns})
    return buffer.getvalue()


output = to_csv(
    [{"id": 1, "name": "ada"}, {"id": 2}],
    ["id", "name", "email"],
)
print(output)

Related Examples