Method Case
View SourceCase<TValue, TResult>(Func<TValue>, IDictionary<TValue, IAsyncEnumerable<TResult>>)
Returns a sequence from a dictionary based on the result of evaluating a selector function.
Declaration
public static IAsyncEnumerable<TResult> Case<TValue, TResult>(Func<TValue> selector, IDictionary<TValue, IAsyncEnumerable<TResult>> sources) where TValue : notnullParameters
| Type | Name | Description |
|---|---|---|
| Func<TValue> | selector | Selector function used to pick a sequence from the given sources. |
| IDictionary<TValue, IAsyncEnumerable<TResult>> | sources | Dictionary mapping selector values onto resulting sequences. |
Returns
| Type | Description |
|---|---|
| IAsyncEnumerable<TResult> | The source sequence corresponding with the evaluated selector value; otherwise, an empty sequence. |
Type Parameters
| Name | Description |
|---|---|
| TValue | Type of the selector value. |
| TResult | Result sequence element type. |
Remarks
selector is not evaluated until enumeration. The value returned will be used to select a
sequence from sources; enumeration will continue with items from that sequence.
If the value returned by selector is not present in sources, the resulting
sequence will be empty.
Exceptions
| Type | Condition |
|---|---|
| ArgumentNullException |
|
Case<TValue, TResult>(Func<ValueTask<TValue>>, IDictionary<TValue, IAsyncEnumerable<TResult>>)
Returns a sequence from a dictionary based on the result of evaluating a selector function.
Declaration
public static IAsyncEnumerable<TResult> Case<TValue, TResult>(Func<ValueTask<TValue>> selector, IDictionary<TValue, IAsyncEnumerable<TResult>> sources) where TValue : notnullParameters
| Type | Name | Description |
|---|---|---|
| Func<ValueTask<TValue>> | selector | Selector function used to pick a sequence from the given sources. |
| IDictionary<TValue, IAsyncEnumerable<TResult>> | sources | Dictionary mapping selector values onto resulting sequences. |
Returns
| Type | Description |
|---|---|
| IAsyncEnumerable<TResult> | The source sequence corresponding with the evaluated selector value; otherwise, an empty sequence. |
Type Parameters
| Name | Description |
|---|---|
| TValue | Type of the selector value. |
| TResult | Result sequence element type. |
Remarks
selector is not evaluated until enumeration. The value returned will be used to select a
sequence from sources; enumeration will continue with items from that sequence.
If the value returned by selector is not present in sources, the resulting
sequence will be empty.
Exceptions
| Type | Condition |
|---|---|
| ArgumentNullException |
|
Case<TValue, TResult>(Func<TValue>, IDictionary<TValue, IAsyncEnumerable<TResult>>, IAsyncEnumerable<TResult>)
Returns a sequence from a dictionary based on the result of evaluating a selector function.
Declaration
public static IAsyncEnumerable<TResult> Case<TValue, TResult>(Func<TValue> selector, IDictionary<TValue, IAsyncEnumerable<TResult>> sources, IAsyncEnumerable<TResult> defaultSource) where TValue : notnullParameters
| Type | Name | Description |
|---|---|---|
| Func<TValue> | selector | Selector function used to pick a sequence from the given sources. |
| IDictionary<TValue, IAsyncEnumerable<TResult>> | sources | Dictionary mapping selector values onto resulting sequences. |
| IAsyncEnumerable<TResult> | defaultSource | Default sequence to return in case there's no corresponding source for the computed selector value. |
Returns
| Type | Description |
|---|---|
| IAsyncEnumerable<TResult> | The source sequence corresponding with the evaluated selector value; otherwise, an empty sequence. |
Type Parameters
| Name | Description |
|---|---|
| TValue | Type of the selector value. |
| TResult | Result sequence element type. |
Remarks
selector is not evaluated until enumeration. The value returned will be used to select a
sequence from sources; enumeration will continue with items from that sequence.
Exceptions
| Type | Condition |
|---|---|
| ArgumentNullException |
|
Case<TValue, TResult>(Func<ValueTask<TValue>>, IDictionary<TValue, IAsyncEnumerable<TResult>>, IAsyncEnumerable<TResult>)
Returns a sequence from a dictionary based on the result of evaluating a selector function.
Declaration
public static IAsyncEnumerable<TResult> Case<TValue, TResult>(Func<ValueTask<TValue>> selector, IDictionary<TValue, IAsyncEnumerable<TResult>> sources, IAsyncEnumerable<TResult> defaultSource) where TValue : notnullParameters
| Type | Name | Description |
|---|---|---|
| Func<ValueTask<TValue>> | selector | Selector function used to pick a sequence from the given sources. |
| IDictionary<TValue, IAsyncEnumerable<TResult>> | sources | Dictionary mapping selector values onto resulting sequences. |
| IAsyncEnumerable<TResult> | defaultSource | Default sequence to return in case there's no corresponding source for the computed selector value. |
Returns
| Type | Description |
|---|---|
| IAsyncEnumerable<TResult> | The source sequence corresponding with the evaluated selector value; otherwise, an empty sequence. |
Type Parameters
| Name | Description |
|---|---|
| TValue | Type of the selector value. |
| TResult | Result sequence element type. |
Remarks
selector is not evaluated until enumeration. The value returned will be used to select a
sequence from sources; enumeration will continue with items from that sequence.
Exceptions
| Type | Condition |
|---|---|
| ArgumentNullException |
|