Method PadStart
PadStart<TSource>(IAsyncEnumerable<TSource>, int)
Pads a sequence with default values in the beginning if it is narrower (shorter in length) than a given width.
Declaration
public static IAsyncEnumerable<TSource?> PadStart<TSource>(this IAsyncEnumerable<TSource> source, int width)Parameters
| Type | Name | Description |
|---|---|---|
| IAsyncEnumerable<TSource> | source | The sequence to pad. |
| int | width | The width/length below which to pad. |
Returns
| Type | Description |
|---|---|
| IAsyncEnumerable<TSource> | Returns a sequence that is at least as wide/long as the width/length
specified by the |
Type Parameters
| Name | Description |
|---|---|
| TSource | The type of the elements of |
Remarks
This operator uses deferred execution and streams its results.
Examples
int[] numbers = { 123, 456, 789 };
var result = numbers.PadStart(5);The result variable will contain { 0, 0, 123, 456, 789 }.
Exceptions
| Type | Condition |
|---|---|
| ArgumentNullException |
|
| ArgumentOutOfRangeException |
|
PadStart<TSource>(IAsyncEnumerable<TSource>, int, TSource)
Pads a sequence with a given filler value in the beginning if it is narrower (shorter in length) than a given width. An additional parameter specifies the value to use for padding.
Declaration
public static IAsyncEnumerable<TSource> PadStart<TSource>(this IAsyncEnumerable<TSource> source, int width, TSource padding)Parameters
| Type | Name | Description |
|---|---|---|
| IAsyncEnumerable<TSource> | source | The sequence to pad. |
| int | width | The width/length below which to pad. |
| TSource | padding | The value to use for padding. |
Returns
| Type | Description |
|---|---|
| IAsyncEnumerable<TSource> | Returns a sequence that is at least as wide/long as the width/length
specified by the |
Type Parameters
| Name | Description |
|---|---|
| TSource | The type of the elements of |
Remarks
This operator uses deferred execution and streams its results.
Examples
int[] numbers = { 123, 456, 789 };
var result = numbers.PadStart(5, -1);The result variable will contain { -1, -1, 123, 456, 789 }.
Exceptions
| Type | Condition |
|---|---|
| ArgumentNullException |
|
| ArgumentOutOfRangeException |
|
PadStart<TSource>(IAsyncEnumerable<TSource>, int, Func<int, TSource>)
Pads a sequence with a dynamic filler value in the beginning if it is narrower (shorter in length) than a given width. An additional parameter specifies the function to calculate padding.
Declaration
public static IAsyncEnumerable<TSource> PadStart<TSource>(this IAsyncEnumerable<TSource> source, int width, Func<int, TSource> paddingSelector)Parameters
| Type | Name | Description |
|---|---|---|
| IAsyncEnumerable<TSource> | source | The sequence to pad. |
| int | width | The width/length below which to pad. |
| Func<int, TSource> | paddingSelector | Function to calculate padding given the index of the missing element. |
Returns
| Type | Description |
|---|---|
| IAsyncEnumerable<TSource> | Returns a sequence that is at least as wide/long as the width/length
specified by the |
Type Parameters
| Name | Description |
|---|---|
| TSource | The type of the elements of |
Remarks
This operator uses deferred execution and streams its results.
Examples
int[] numbers = { 123, 456, 789 };
var result = numbers.PadStart(6, i => -i);The result variable will contain { 0, -1, -2, 123, 456, 789 }.
Exceptions
| Type | Condition |
|---|---|
| ArgumentNullException |
|
| ArgumentNullException |
|
| ArgumentOutOfRangeException |
|