public async Task TestMethod1Async()
{
await using var inCsf = new FileStream("InCsf.csf", FileMode.Open);
await using var outJson = new FileStream("OutJson.json", FileMode.Create);
await using var outCsf = new FileStream("OutCsf.csf", FileMode.Create);
var csfStruct = CsfStructUtils.Serialize(inCsf);
var options = CsfJsonConverterUtils.CsfJsonSerializerOptions;
await JsonSerializer.SerializeAsync(outJson, csfStruct, options);
outJson.Seek(0, SeekOrigin.Begin);
var csfStruct1 = await JsonSerializer.DeserializeAsync <CsfStruct>(outJson, options);
csfStruct1.Deserialize(outCsf);
}
static Task Csf2Json(Stream input, Stream output) => JsonSerializer.SerializeAsync(output, CsfStructUtils.Serialize(input), CsfJsonConverterUtils.CsfJsonSerializerOptions);