>()
delay(100) //other suspending task
readAllAsSequence().asFlow().collect { row ->
delay(100) // other suspending task
container.add(row)
}
}
```
Note: `openAsync` can be and only be accessed through a `coroutine` or another `suspending` function
**Customize**
When you create CsvReader, you can choose read options:
```kotlin
// this is tsv reader's option
val tsvReader = csvReader {
charset = "ISO_8859_1"
quoteChar = '"'
delimiter = '\t'
escapeChar = '\\'
}
```
| Option | default value | description |
| ------------------------------ | ------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| logger | *no-op* | Logger instance for logging debug information at runtime. |
| charset | `UTF-8` | Charset encoding. The value must be supported by [java.nio.charset.Charset](https://docs.oracle.com/javase/8/docs/api/java/nio/charset/Charset.html). |
| quoteChar | `"` | Character used to quote fields. |
| delimiter | `,` | Character used as delimiter between each field.
Use "\t" if reading TSV file.
|
| escapeChar | `"` | Character to escape quote inside field string.
Normally, you don't have to change this option.
See detail comment on ICsvReaderContext.
|
| skipEmptyLine | `false` | Whether to skip or error out on empty lines. |
| autoRenameDuplicateHeaders | `false` | Whether to auto rename duplicate headers or throw an exception. |
| ~~skipMissMatchedRow~~ | `false` | Deprecated. Replace with appropriate values in `excessFieldsRowBehaviour` and `insufficientFieldsRowBehaviour`, e.g. both set to `IGNORE`. ~~Whether to skip an invalid row. If `ignoreExcessCols` is true, only rows with less than the expected number of columns will be skipped.~~ |
| excessFieldsRowBehaviour | `ERROR` | Behaviour to use when a row has more fields (columns) than expected. `ERROR` (default), `IGNORE` (skip the row) or `TRIM` (remove the excess fields at the end of the row to match the expected number of fields). |
| insufficientFieldsRowBehaviour | `ERROR` | Behaviour to use when a row has fewer fields (columns) than expected. `ERROR` (default), `IGNORE` (skip the row) or `EMPTY_STRING` (replace missing fields with an empty string). |
#### CSV Write examples
**Simple case**
You can start writing csv in one line, no need to do any I/O handling (No need to call `use`, `close` and `flush` method.):
```kotlin
val rows = listOf(listOf("a", "b", "c"), listOf("d", "e", "f"))
csvWriter().writeAll(rows, "test.csv")
// if you'd append data on the tail of the file, assign `append = true`.
csvWriter().writeAll(rows, "test.csv", append = true)
// You can also write into OutpusStream.
csvWriter().writeAll(rows, File("test.csv").outputStream())
```
You can also write a csv file line by line by `open` method:
```kotlin
val row1 = listOf("a", "b", "c")
val row2 = listOf("d", "e", "f")
csvWriter().open("test.csv") {
writeRow(row1)
writeRow(row2)
writeRow("g", "h", "i")
writeRows(listOf(row1, row2))
}
```
**Write in a `Suspending Function`**
```kotlin
val rows = listOf(listOf("a", "b", "c"), listOf("d", "e", "f")).asSequence()
csvWriter().openAsync(testFileName) {
delay(100) //other suspending task
rows.asFlow().collect {
delay(100) // other suspending task
writeRow(it)
}
}
```
**Write as String**
```kotlin
val rows = listOf(listOf("a", "b", "c"), listOf("d", "e", "f"))
val csvString: String = csvWriter().writeAllAsString(rows) //a,b,c\r\nd,e,f\r\n
```
**long-running write (manual control for file close)**
If you want to close a file writer manually for performance reasons (e.g. streaming scenario), you can use `openAndGetRawWriter` and get a raw `CsvFileWriter`.\
**DO NOT forget to `close` the writer!**
```kotlin
val row1 = listOf("a", "b", "c")
@OptIn(KotlinCsvExperimental::class)
val writer = csvWriter().openAndGetRawWriter("test.csv")
writer.writeRow(row1)
writer.close()
```
**Customize**
When you create a CsvWriter, you can choose write options.
```kotlin
val writer = csvWriter {
charset = "ISO_8859_1"
delimiter = '\t'
nullCode = "NULL"
lineTerminator = "\n"
outputLastLineTerminator = true
quote {
mode = WriteQuoteMode.ALL
char = '\''
}
}
```
| Option | default value | description |
| ------------------------ | ---------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| charset | `UTF-8` | Charset encoding. The value must be supported by [java.nio.charset.Charset](https://docs.oracle.com/javase/8/docs/api/java/nio/charset/Charset.html). |
| delimiter | `,` | Character used as delimiter between each fields.
Use "\t" if reading TSV file.
|
| nullCode | `(empty string)` | Character used when a written field is null value. |
| lineTerminator | `\r` | Character used as line terminator. |
| outputLastLineTerminator | `true` | Output line break at the end of file or not. |
| prependBOM | `false` | Output BOM (Byte Order Mark) at the beginning of file or not. |
| quote.char | `"` | Character to quote each fields. |
| quote.mode | `CANONICAL` | Quote mode.
- CANONICAL: Not quote normally, but quote special characters (quoteChar, delimiter, line feed). This is the specification of CSV.
- ALL: Quote all fields.
- NON\_NUMERIC: Quote non-numeric fields. (ex. 1,"a",2.3)
|
## Links
**Documents**
* [Change Logs](https://github.com/doyaaaaaken/kotlin-csv/releases)
**Libraries which use kotlin-csv**
* [kotlin-grass](https://github.com/blackmo18/kotlin-grass): Csv File to Kotlin Data Class Parser.
## Miscellaneous
### 🤝 Contributing
Contributions, [issues](https://github.com/doyaaaaaken/kotlin-csv/issues) and feature requests are welcome! If you have questions, ask away in [Kotlin Slack's](https://kotlinlang.slack.com) `kotlin-csv` room.
### 💻 Development
```sh
git clone git@github.com:doyaaaaaken/kotlin-csv.git
cd kotlin-csv
./gradlew check
```
### Show your support
Give a ⭐️ if this project helped you!
### 📝 License
Copyright © 2024 [jsoizo](https://github.com/jsoizo). This project is licensed under [Apache 2.0](https://github.com/doyaaaaaken/kotlin-csv/blob/master/LICENSE/README.md).
***
*This project is inspired ❤️ by* [*scala-csv*](https://github.com/tototoshi/scala-csv)
*This README was generated with ❤️ by* [*readme-md-generator*](https://github.com/kefranabg/readme-md-generator)
### Acknowledgments
This project was originally created by [@doyaaaaaken](https://github.com/doyaaaaaken). The initial work and contributions are greatly appreciated.
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