Field parser

Use the Field parser to modify the value of a field being imported from a CSV row. The field parser function returns the text value that gets imported. If the field is mapped to a column having a non-string data type, the returned text must be convertible to the target column data type as defined in Column mappings.

The Field parser function has the following signature:

public static string? ParseFieldValue(string? text, int fieldIndex, FieldParserContext context)
{
    // TODO: Implement your custom parser logic    
    return text;
}

Parameters

Name	Data type	Description
text	string	The value of the field from the CSV row. As the signature implies, the value may be null.
fieldIndex	int	The index of the field in the record. Note that the index is 1-based, so the first field has index 1.
context	FieldParserContext	Provides access to additional APIs that can be used during parsing of a field value.

FieldParserContext properties

Name	Data type	Description
Record	string []	All fields in the record reprsented as an array of strings.
Diagnostics	IDiagnosticsServices	Provides access to the diagnostics API, which can be used for logging an debugging.

Example

This example shows two different use cases for the field parser.

1. Our CSV file contains fields with the value "..", which we need to interpret as null in our example.
2. We need to combine the values in field 8 and 11 to a new value when the CSV file is imported.

public static string? ParseFieldValue(string? text, int fieldIndex, FieldParserContext context)
{
    if(text == "..")
    {
        return null;
    }

    // Our Column mapping does not include field index 11, so we don't have to handle that case.
    if(fieldIndex == 8) 
    {
        // context.Record is a string array. 
        // Array indexes are always 0-based, so the 8th field is at index 7 and the 11th field is at index 10 in the array.
        return string.Concat(context.Record[7], "_", context.Record[10]);
    }
    
    return text;
}