---
title: ColumnPreferenceList
summary: API reference for ColumnPreferenceList.
status: draft
owner: SAIF documentation generator
last_reviewed: 2026-08-17
library: SAIF.Presentation.Web.Controls.AJAX.Infragistics103
reference_type: package
---

# ColumnPreferenceList

`ColumnPreferenceList` serializes and deserializes a grid's column-visibility selections to/from a compact, semicolon/period-delimited string, letting `InfragisticsGridCustomizer` persist and reload user preferences through `clsPreferences` without needing a structured storage format.

## Purpose
- Converts a checkbox-list selection (`ListItemCollection` or `Generic.List(Of ListItem)`) into a delimited preference string via `ToString()`, and parses that same string format back into structured `Preference` entries via its string constructor.
- Provides duplicate-safe `Add` overloads so the same column key is never recorded twice in a preference list.

## Context
- Namespace: `SAIF.Presentation.Web.Controls.V2.AJAX`
- Assembly/package: `SAIF.Presentation.Web.Controls.AJAX.Infragistics103`

## Public members
| Member | Signature | Purpose |
| --- | --- | --- |
| DefaultColumnDataDelimiter | `Public Const DefaultColumnDataDelimiter As Char = ";"c` | Delimiter separating individual column preference entries |
| DefaultColumnDataSubDelimiter | `Public Const DefaultColumnDataSubDelimiter As Char = "."c` | Delimiter separating a column key from its selected-state flag within one entry |
| New (ListItemCollection) | `Sub New(inListItems As ListItemCollection)` | Builds the preference list from a checkbox-list control's items and their selected state |
| New (Generic.List(Of ListItem)) | `Sub New(inListItems As Generic.List(Of ListItem))` | Builds the preference list from an in-memory list of `ListItem`s and their selected state |
| New (String) | `Sub New(inColumnPreferenceData As String)` | Parses a previously-serialized preference string back into structured `Preference` entries |
| ToString | `Overrides Function ToString() As String` | Serializes the current preference entries into the delimited string format used for persistence |
| Add (Preference) | `Shadows Function Add(inColumnPreference As Preference) As Boolean` | Adds a preference entry, returning `False` if a preference for that column key already exists |
| Add (String, Boolean) | `Shadows Function Add(inColumnKey As String, inIsSelected As Boolean) As Boolean` | Adds a preference entry by column key and selected flag, guarding against duplicates |
| Contains | `Overloads Function Contains(inColumnKey As String) As Boolean` | Indicates whether a preference entry already exists for the given column key |

## Inherited public members

Members in this section are inherited from `Generic.List(Of Preference)` in the .NET Framework Base Class Library. They are available on this type through inheritance.

| Member | Signature | Purpose | Origin |
| --- | --- | --- | --- |
| Count | `ReadOnly Property Count As Integer` | The number of preference entries currently in the list | `mscorlib` — `System.Collections.Generic.List(Of T)` |
| Item | `Default Property Item(index As Integer) As Preference` | Positional access to a parsed column-key/selected-state entry, used when replaying or rewriting entries by position | `mscorlib` — `System.Collections.Generic.List(Of T)` |
| Remove | `Function Remove(item As Preference) As Boolean` | Removes the first occurrence of the given preference entry from the list | `mscorlib` — `System.Collections.Generic.List(Of T)` |
| Clear | `Sub Clear()` | Removes all preference entries from the list | `mscorlib` — `System.Collections.Generic.List(Of T)` |
| GetEnumerator | `Function GetEnumerator() As List(Of Preference).Enumerator` | Supports `For Each` iteration over the preference entries | `mscorlib` — `System.Collections.Generic.List(Of T)` |

## Behavioral notes
- `ToString()` trims the trailing delimiter from the final serialized string, so an empty list would raise an index-out-of-range error if called with zero entries*.

## Constraints and usage notes
- The string constructor expects exactly the delimiter format produced by `ToString()`; malformed input (missing sub-delimiter) will throw an index error when parsing `columnData(1)`.

> **Note:** Statements marked with * were inferred from code structure, naming conventions, or
> contextual evidence where direct confirmation was not available in source artifacts. Statements
> marked with ** could not be confirmed; treat as unknown until verified.

## Sources
- `SAIF.Presentation.Web.Controls.AJAX.Infragistics103\InfragisticsGridCustomizer.vb`