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// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
#nullable enable
using Microsoft.AspNetCore.Mvc.Core;
namespace Microsoft.AspNetCore.Mvc.ModelBinding;
/// <summary>
/// A value provider which provides data from a specific <see cref="BindingSource"/>.
/// </summary>
/// <remarks>
/// <para>
/// A <see cref="BindingSourceValueProvider"/> is an <see cref="IValueProvider"/> base-implementation which
/// can provide data for all parameters and model properties which specify the corresponding
/// <see cref="ModelBinding.BindingSource"/>.
/// </para>
/// <para>
/// <see cref="BindingSourceValueProvider"/> implements <see cref="IBindingSourceValueProvider"/> and will
/// include or exclude itself from the set of value providers based on the model's associated
/// <see cref="ModelBinding.BindingSource"/>. Value providers are by-default included; if a model does not
/// specify a <see cref="ModelBinding.BindingSource"/> then all value providers are valid.
/// </para>
/// </remarks>
public abstract class BindingSourceValueProvider : IBindingSourceValueProvider
{
/// <summary>
/// Creates a new <see cref="BindingSourceValueProvider"/>.
/// </summary>
/// <param name="bindingSource">
/// The <see cref="ModelBinding.BindingSource"/>. Must be a single-source (non-composite) with
/// <see cref="ModelBinding.BindingSource.IsGreedy"/> equal to <c>false</c>.
/// </param>
public BindingSourceValueProvider(BindingSource bindingSource)
{
ArgumentNullException.ThrowIfNull(bindingSource);
if (bindingSource.IsGreedy)
{
var message = Resources.FormatBindingSource_CannotBeGreedy(
bindingSource.DisplayName,
nameof(BindingSourceValueProvider));
throw new ArgumentException(message, nameof(bindingSource));
}
if (bindingSource is CompositeBindingSource)
{
var message = Resources.FormatBindingSource_CannotBeComposite(
bindingSource.DisplayName,
nameof(BindingSourceValueProvider));
throw new ArgumentException(message, nameof(bindingSource));
}
BindingSource = bindingSource;
}
/// <summary>
/// Gets the corresponding <see cref="ModelBinding.BindingSource"/>.
/// </summary>
protected BindingSource BindingSource { get; }
/// <inheritdoc />
public abstract bool ContainsPrefix(string prefix);
/// <inheritdoc />
public abstract ValueProviderResult GetValue(string key);
/// <inheritdoc />
public virtual IValueProvider? Filter(BindingSource bindingSource)
{
ArgumentNullException.ThrowIfNull(bindingSource);
if (bindingSource.CanAcceptDataFrom(BindingSource))
{
return this;
}
else
{
return null;
}
}
}
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