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Use Streaming and Column-qualified Formats

Structures and containers are data types that contain multiple elements. Luban provides four ways to read this composite data type:

  • Streaming format, multiple cells, read in order

  • Streaming format, one cell, read in order after splitting with a delimiter

  • Column-qualified format, multiple cells, explicitly specify the column occupied by each field, and then read

  • Read multiple rows. This method is only valid for container types. You can use the above three methods to read when reading elements

For detailed data documents, see Excel Format (Advanced).

Preparatory work​

Assume that the Item structure contains two fields, item_id and count. We will demonstrate the usage of streaming and column-qualified modes related to the Item structure later.

Streaming format, multiple cells, read in order​

The streaming format has a feature: it reads each element (field) of the composite data in order. Since it cannot limit the range of each field, it will skip all blank cells it reads. This is not a problem when there are not many fields, but when there are more fields, it is easy to cause subsequent field reading errors due to missing a field.

For example, the following item field filling method, whether inserting an empty cell at the beginning, middle, or end, does not affect data reading.

item

Streaming format, one cell, read in sequence after splitting with delimiter​

After splitting with sep, treat each data as a cell, and its filling method is the same as the first method.

item

Limited column format, multiple cells, explicitly specify the columns occupied by each field, and then read​

Specify the columns of subfields for the structure by adding a subheader line. The first column of the subheader line must be '##var'.

item

tip

The column-limited format can have multiple layers of *: that is, if a subfield of a structure is also a structure, you can still add a sub-header row to specify the column for the subfield of the subfield.

Multi-row reading​

Only container types can use multi-row reading. Adding '*' before the field name indicates that this field is read in multi-row mode. When reading each row of data, both streaming format and column-limited format are supported.

item