Constraint.cs

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using System.ComponentModel;
using System.Data.Common;
using System.Diagnostics.CodeAnalysis;
using System.Globalization;
 
namespace System.Data;
 
[DefaultProperty("ConstraintName")]
[TypeConverter(typeof(ConstraintConverter))]
public abstract class Constraint
{
    private string _schemaName = string.Empty;
 
    private bool _inCollection;
 
    private DataSet _dataSet;
 
    internal string _name = string.Empty;
 
    internal PropertyCollection _extendedProperties;
 
    [DefaultValue("")]
    public virtual string ConstraintName
    {
        get
        {
            return _name;
        }
        [param: AllowNull]
        set
        {
            if (value == null)
            {
                value = string.Empty;
            }
            if (string.IsNullOrEmpty(value) && Table != null && InCollection)
            {
                throw ExceptionBuilder.NoConstraintName();
            }
            CultureInfo culture = ((Table != null) ? Table.Locale : CultureInfo.CurrentCulture);
            if (string.Compare(_name, value, ignoreCase: true, culture) != 0)
            {
                if (Table != null && InCollection)
                {
                    Table.Constraints.RegisterName(value);
                    if (_name.Length != 0)
                    {
                        Table.Constraints.UnregisterName(_name);
                    }
                }
                _name = value;
            }
            else if (string.Compare(_name, value, ignoreCase: false, culture) != 0)
            {
                _name = value;
            }
        }
    }
 
    internal string SchemaName
    {
        get
        {
            if (!string.IsNullOrEmpty(_schemaName))
            {
                return _schemaName;
            }
            return ConstraintName;
        }
        set
        {
            if (!string.IsNullOrEmpty(value))
            {
                _schemaName = value;
            }
        }
    }
 
    internal virtual bool InCollection
    {
        get
        {
            return _inCollection;
        }
        set
        {
            _inCollection = value;
            _dataSet = (value ? Table.DataSet : null);
        }
    }
 
    public abstract DataTable? Table { get; }
 
    [Browsable(false)]
    public PropertyCollection ExtendedProperties => _extendedProperties ?? (_extendedProperties = new PropertyCollection());
 
    [CLSCompliant(false)]
    protected virtual DataSet? _DataSet => _dataSet;
 
    internal Constraint()
    {
    }
 
    internal abstract bool ContainsColumn(DataColumn column);
 
    internal abstract bool CanEnableConstraint();
 
    internal abstract Constraint Clone(DataSet destination);
 
    internal abstract Constraint Clone(DataSet destination, bool ignoreNSforTableLookup);
 
    internal void CheckConstraint()
    {
        if (!CanEnableConstraint())
        {
            throw ExceptionBuilder.ConstraintViolation(ConstraintName);
        }
    }
 
    internal abstract void CheckCanAddToCollection(ConstraintCollection constraint);
 
    internal abstract bool CanBeRemovedFromCollection(ConstraintCollection constraint, bool fThrowException);
 
    internal abstract void CheckConstraint(DataRow row, DataRowAction action);
 
    internal abstract void CheckState();
 
    protected void CheckStateForProperty()
    {
        try
        {
            CheckState();
        }
        catch (Exception ex) when (ADP.IsCatchableExceptionType(ex))
        {
            throw ExceptionBuilder.BadObjectPropertyAccess(ex.Message);
        }
    }
 
    protected internal void SetDataSet(DataSet dataSet)
    {
        _dataSet = dataSet;
    }
 
    internal abstract bool IsConstraintViolated();
 
    public override string ToString()
    {
        return ConstraintName;
    }
}