Syntax

A text file data reader.

Remarks

A class that implements IDataReader must implement the Read() and IDataRecord GetValue() methods. It must also implement the IDataRecord FieldCount property.

The GetOrdinal() method must be implemented if field name mapping is used.

The currently supported common IDataReader methods are: GetDataTypeName(int/string), GetFieldType(), GetName(), GetOrdinal(), GetSchemaTable(), GetValues(), IsDBNull() and Read().
All IDataRecord Get Type by index methods are supported including: GetBoolean(), GetInt32(), GetString(), GetValue(), etc.

Also included are custom Get Type by name method overloads to get the data values by the field name. These methods overload the IDataRecord Get Type by index methods.

This data reader expects the lines to be terminated with CR/LF. It can parse comma or tab delimited fields and can handle quoted fields.
Only use quoted fields when necessary to get a slight performance increase.

Use the LJCSetFile() method to initialize for the file to be read. This sets the LJCDataFields property with the data field definitions. Use the Read() method to read the next line values from the file.

Alternately, you can use the LJCSetLines() method if you want to process a string array. Use the LJCReadLine() method to read the next line from the string array.

The data field definition names can be parsed from the file heading line. This can be accomplished in two ways:
1. When creating the TextDataReader, set the hasheadingLine constructor property to 'true' or leave it blank to let it default to 'true'.
2. After creating the TextDataReader, you can set the LJCHasHeadingLine property to 'true'. This must be done before calling the LJCSetFile() or LJCSetLines() method.

The data fields can be in a fixed length format. This can be set in two ways:
1. When creating the TextDataReader, set the fixedLengthFields constructor property to 'true'.
2. After creating the TextDataReader, you can set the LJCFixedLengthFields property to 'true'. This must be done before calling the LJCSetFile() or LJCSetLines() method.
The field MaxLength and DataTypeName can be included in the file heading line. The formats are: Name|MaxLength or Name|MaxLength|DataTypeName. The MaxLength value is required for fixed length fields.

The data field definitions can also be loaded from an XML layout file.
Use the LJCSetFields() method to initialize the data field definitions from an XML data definition file. This file uses the DbColumns format.
Set LJCHasHeaderLine to 'false' before calling LJCSetFile() or LJCSetLines().
The MaxLength and Position values are required for fixed length fields.
The field names can be retrieved with the LJCGetFieldNames() method.

The Read() or LJCReadLine() methods set the next line values in the LJCDataFields property. A field value can be retrieved by index or field name as in object value = textDataReader[1]; or value = textDataReader["Name"];. A value can also be retrieved as a specific type by index or name using the Get Type methods such as GetBoolean(), GetInt32(), GetString(), GetValue(), etc.

A Data Object can be populated with the field values using the LJCSetObjectValues() method.

54 Methods