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//------------------------------------------------------------------------------
// <copyright file="DataColumnPropertyDescriptor.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.Diagnostics;
using System.ComponentModel;
using System.Data.Common;
internal sealed class DataColumnPropertyDescriptor : PropertyDescriptor {
DataColumn column;
internal DataColumnPropertyDescriptor(DataColumn dataColumn) : base(dataColumn.ColumnName, null) {
this.column = dataColumn;
}
public override AttributeCollection Attributes {
get {
if (typeof(System.Collections.IList).IsAssignableFrom(this.PropertyType)) {
Attribute[] attrs = new Attribute[base.Attributes.Count + 1];
base.Attributes.CopyTo(attrs, 0);
// we don't want to show the columns which are of type IList in the designer
attrs[attrs.Length - 1] = new ListBindableAttribute(false);
return new AttributeCollection(attrs);
} else {
return base.Attributes;
}
}
}
internal DataColumn Column {
get {
return column;
}
}
public override Type ComponentType {
get {
return typeof(DataRowView);
}
}
public override bool IsReadOnly {
get {
return column.ReadOnly;
}
}
public override Type PropertyType {
get {
return column.DataType;
}
}
public override bool Equals(object other) {
if (other is DataColumnPropertyDescriptor) {
DataColumnPropertyDescriptor descriptor = (DataColumnPropertyDescriptor) other;
return(descriptor.Column == Column);
}
return false;
}
public override Int32 GetHashCode() {
return Column.GetHashCode();
}
public override bool CanResetValue(object component) {
DataRowView dataRowView = (DataRowView) component;
if (!column.IsSqlType)
return (dataRowView.GetColumnValue(column) != DBNull.Value);
return (!DataStorage.IsObjectNull(dataRowView.GetColumnValue(column)));
}
public override object GetValue(object component) {
DataRowView dataRowView = (DataRowView) component;
return dataRowView.GetColumnValue(column);
}
public override void ResetValue(object component) {
DataRowView dataRowView = (DataRowView) component;
dataRowView.SetColumnValue(column, DBNull.Value);// no need to ccheck for the col type and set Sql...Null!
}
public override void SetValue(object component, object value) {
DataRowView dataRowView = (DataRowView) component;
dataRowView.SetColumnValue(column, value);
OnValueChanged(component, EventArgs.Empty);
}
public override bool ShouldSerializeValue(object component) {
return false;
}
public override bool IsBrowsable {
get {
return (column.ColumnMapping == System.Data.MappingType.Hidden ? false : base.IsBrowsable);
}
}
}
}
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