AddColumns Method

Overview

The AddColumns method adds multiple columns to the table by calling AddColumn for each metadata entry.

It is useful when you already have a list of prepared IColumnMetadata instances (for example, when cloning schema from another table).

Declaration

/// <summary>
/// Adds columns
/// </summary>
/// <param name="listOfColumnMetadata">List of column metadata</param>
public void AddColumns(IReadOnlyList<IColumnMetadata> listOfColumnMetadata)

Namespace and Assembly

Namespace: PocoDataSet.Data
Assembly: PocoDataSet.Data.dll

Behavior

• Iterates through listOfColumnMetadata and calls AddColumn(IColumnMetadata) for each entry.
• For each added column, ensures existing rows have the new column key (adds null when missing).
• Throws if any column name duplicates an existing column name.

Usage Example

using System.Collections.Generic;
using PocoDataSet.Data;
using PocoDataSet.IData;

DataTable source = new DataTable();
source.TableName = "Employee";
source.AddColumn("Id", DataTypeNames.INT32, isNullable: false, isPrimaryKey: true);
source.AddColumn("Name", DataTypeNames.STRING, isNullable: true);

// Prepare metadata list (example: copy from source schema)
List<IColumnMetadata> cols = new List<IColumnMetadata>();
for (int i = 0; i < source.Columns.Count; i++)
{
cols.Add(source.Columns[i].Clone());
}

DataTable target = new DataTable();
target.TableName = "Employee";
target.AddColumns(cols);

Notes

• If you are building schema from scratch, calling AddColumn repeatedly is equivalent.
• If you add columns after data is loaded, row back-fill keeps row dictionaries aligned with the new schema.

 

Table of Content POCO DataSet API References POCO DataSet Types DataTable Members

 

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Business Process Programming in .Net
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