TryFindRowByPrimaryKey Method

Overview

The TryFindRowByPrimaryKey extension method searches a table for a row whose primary key column(s) match specified value(s).

It performs a linear scan of dataTable.Rows and supports both single-column and composite primary keys.

Declaration

/// <summary>
/// Tries to find a row by primary key values by scanning table rows.
/// Works for single or composite primary keys.
/// </summary>
public static bool TryFindRowByPrimaryKey(this IDataTable? dataTable, List<string> primaryKeyColumnNames, object?[] primaryKeyValues, out IDataRow? foundRow)

/// <summary>
/// Convenience overload for single-column primary keys.
/// </summary>
public static bool TryFindRowByPrimaryKey(this IDataTable? dataTable, string primaryKeyColumnName, object? primaryKeyValue, out IDataRow? foundRow)

Namespace and Assembly

Namespace: PocoDataSet.Extensions
Assembly: PocoDataSet.Extensions.dll

Behavior

• Returns false if dataTable is null.
• Returns false if primaryKeyColumnNames is null/empty, or if the number of column names does not match the number of values.
• For each row, reads each key value using GetDataFieldValue<T> and compares against the expected value.
• Treats DBNull.Value as null for comparison purposes.
• Uses Equals for equality; does not perform type coercion (so pass values of the correct type).

Usage Example

using PocoDataSet.Data;
using PocoDataSet.Extensions;
using PocoDataSet.IData;

DataTable table = new DataTable();
table.TableName = "Employee";
table.AddColumn("Id", "Int32", isNullable: false, isPrimaryKey: true);
table.AddColumn("Name", "String");

var r1 = table.AddNewRow();
r1["Id"] = 1;
r1["Name"] = "Ada";
r1.AcceptChanges();

var r2 = table.AddNewRow();
r2["Id"] = 2;
r2["Name"] = "Alan";
r2.AcceptChanges();

IDataRow? found;
bool ok = table.TryFindRowByPrimaryKey("Id", 2, out found);
if (ok)
{
// found["Name"] == "Alan"
}

// Composite key example:
// List<string> pk = new List<string> { "TenantId", "EmployeeId" };
// object?[] values = new object?[] { 10, 2 };
// table.TryFindRowByPrimaryKey(pk, values, out found);

Notes

This method performs a linear scan. For frequent lookups on large tables, consider building an index (for example, by using your BuildPrimaryKeyIndex extension where appropriate).

If primary key values may differ in type (e.g., int vs long), normalize your input values before calling, because comparison uses Equals.

 

Table of Content POCO DataSet DataTable Extensions Group DataTable Members

 

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Business Process Programming in .Net
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