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//------------------------------------------------------------------------------
// <copyright file="DataKey.cs" company="Microsoft">
// Copyright (c) Microsoft Corporation. All rights reserved.
// </copyright>
// <owner current="true" primary="true">Microsoft</owner>
// <owner current="true" primary="false">Microsoft</owner>
// <owner current="false" primary="false">Microsoft</owner>
//------------------------------------------------------------------------------
namespace System.Data {
using System;
using System.Diagnostics;
using System.ComponentModel;
internal struct DataKey {
private const int maxColumns = 32;
private readonly DataColumn[] columns;
/// <devdoc>
/// <para>[To be supplied.]</para>
/// </devdoc>
internal DataKey(DataColumn[] columns, bool copyColumns) {
if (columns == null)
throw ExceptionBuilder.ArgumentNull("columns");
if (columns.Length == 0)
throw ExceptionBuilder.KeyNoColumns();
if (columns.Length > maxColumns)
throw ExceptionBuilder.KeyTooManyColumns(maxColumns);
for (int i = 0; i < columns.Length; i++) {
if (columns[i] == null)
throw ExceptionBuilder.ArgumentNull("column");
}
for (int i = 0; i < columns.Length; i++) {
for (int j = 0; j < i; j++) {
if (columns[i] == columns[j]) {
throw ExceptionBuilder.KeyDuplicateColumns(columns[i].ColumnName);
}
}
}
if (copyColumns) {
// Need to make a copy of all columns
this.columns = new DataColumn [columns.Length];
for (int i = 0; i < columns.Length; i++)
this.columns[i] = columns[i];
}
else {
// take ownership of the array passed in
this.columns = columns;
}
CheckState();
}
internal DataColumn[] ColumnsReference {
get {
return columns;
}
}
internal bool HasValue {
get {
return (null != columns);
}
}
internal DataTable Table {
get {
return columns[0].Table;
}
}
internal void CheckState() {
DataTable table = columns[0].Table;
if (table == null) {
throw ExceptionBuilder.ColumnNotInAnyTable();
}
for (int i = 1; i < columns.Length; i++) {
if (columns[i].Table == null) {
throw ExceptionBuilder.ColumnNotInAnyTable();
}
if (columns[i].Table != table) {
throw ExceptionBuilder.KeyTableMismatch();
}
}
}
//check to see if this.columns && key2's columns are equal regardless of order
internal bool ColumnsEqual(DataKey key) {
return ColumnsEqual(this.columns, ((DataKey)key).columns);
}
//check to see if columns1 && columns2 are equal regardless of order
internal static bool ColumnsEqual(DataColumn[] column1, DataColumn[] column2) {
if (column1 == column2) {
return true;
} else if (column1 == null || column2 == null) {
return false;
} else if (column1.Length != column2.Length) {
return false;
} else {
int i, j;
for (i=0; i<column1.Length; i++) {
bool check = false;
for (j=0; j<column2.Length; j++) {
if (column1[i].Equals(column2[j])) {
check = true;
break;
}
}
if (!check) {
return false;
}
}
}
return true;
}
internal bool ContainsColumn(DataColumn column) {
for (int i = 0; i < columns.Length; i++) {
if (column == columns[i]) {
return true;
}
}
return false;
}
public override int GetHashCode() {
Debug.Assert(false, "don't put DataKey into a Hashtable");
return base.GetHashCode();
}
public static bool operator==(DataKey x, DataKey y) {
return x.Equals((object)y);
}
public static bool operator!=(DataKey x, DataKey y) {
return !x.Equals((object)y);
}
public override bool Equals(object value) {
Debug.Assert(false, "need to directly call Equals(DataKey)");
return Equals((DataKey)value);
}
internal bool Equals(DataKey value) {
//check to see if this.columns && key2's columns are equal...
DataColumn[] column1=this.columns;
DataColumn[] column2=value.columns;
if (column1 == column2) {
return true;
}
else if (column1 == null || column2 == null) {
return false;
}
else if (column1.Length != column2.Length) {
return false;
}
else {
for (int i = 0; i <column1.Length; i++) {
if (!column1[i].Equals(column2[i])) {
return false;
}
}
return true;
}
}
internal string[] GetColumnNames() {
string[] values = new string[columns.Length];
for(int i = 0; i < columns.Length; ++i) {
values[i] = columns[i].ColumnName;
}
return values;
}
internal IndexField[] GetIndexDesc() {
IndexField[] indexDesc = new IndexField[columns.Length];
for (int i = 0; i < columns.Length; i++) {
indexDesc[i] = new IndexField(columns[i], false);
}
return indexDesc;
}
internal object[] GetKeyValues(int record) {
object[] values = new object[columns.Length];
for (int i = 0; i < columns.Length; i++) {
values[i] = columns[i][record];
}
return values;
}
internal Index GetSortIndex() {
return GetSortIndex(DataViewRowState.CurrentRows);
}
internal Index GetSortIndex(DataViewRowState recordStates) {
IndexField[] indexDesc = GetIndexDesc();
return columns[0].Table.GetIndex(indexDesc, recordStates, (IFilter)null);
}
internal bool RecordsEqual(int record1, int record2) {
for (int i = 0; i < columns.Length; i++) {
if (columns[i].Compare(record1, record2) != 0) {
return false;
}
}
return true;
}
internal DataColumn[] ToArray() {
DataColumn[] values = new DataColumn[columns.Length];
for(int i = 0; i < columns.Length; ++i) {
values[i] = columns[i];
}
return values;
}
}
}
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