以下是一个使用Python编写的示例代码，用于比较两个CSV文件并将差异写入文件：

import csv

def compare_csv(file1, file2, output_file):
    with open(file1, 'r') as f1:
        csv1 = csv.reader(f1)
        data1 = list(csv1)

    with open(file2, 'r') as f2:
        csv2 = csv.reader(f2)
        data2 = list(csv2)

    differences = []

    for row in data1:
        if row not in data2:
            differences.append(row)

    for row in data2:
        if row not in data1:
            differences.append(row)

    with open(output_file, 'w') as f:
        csv_writer = csv.writer(f)
        csv_writer.writerows(differences)

# 测试示例
compare_csv('file1.csv', 'file2.csv', 'differences.csv')

请确保将file1.csv和file2.csv替换为要比较的实际文件路径，并将differences.csv替换为输出文件的路径。代码将读取两个CSV文件的内容，并将不同的行存储在differences列表中。然后，将differences列表中的内容写入到指定的输出文件中。