MemoryExtensions.StartsWith 方法
定义
重要
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重载
| 名称 | 说明 |
|---|---|
| StartsWith(ReadOnlySpan<Char>, ReadOnlySpan<Char>, StringComparison) |
确定使用指定值比较时，只读字符范围是否以指定 StringComparison 值开头。 |
| StartsWith<T>(ReadOnlySpan<T>, T, IEqualityComparer<T>) |
确定指定值是否出现在范围开头。 |
| StartsWith<T>(ReadOnlySpan<T>, ReadOnlySpan<T>, IEqualityComparer<T>) |
确定指定的序列是否出现在只读范围开始时。 |
| StartsWith<T>(Span<T>, ReadOnlySpan<T>) |
确定指定的序列是否出现在范围开头。 |
| StartsWith<T>(ReadOnlySpan<T>, T) |
确定指定值是否出现在范围开头。 |
| StartsWith<T>(ReadOnlySpan<T>, ReadOnlySpan<T>) |
确定指定的序列是否出现在只读范围开始时。 |
StartsWith(ReadOnlySpan<Char>, ReadOnlySpan<Char>, StringComparison)
确定使用指定值比较时，只读字符范围是否以指定 StringComparison 值开头。
public:
[System::Runtime::CompilerServices::Extension]
static bool StartsWith(ReadOnlySpan<char> span, ReadOnlySpan<char> value, StringComparison comparisonType);public static bool StartsWith(this ReadOnlySpan<char> span, ReadOnlySpan<char> value, StringComparison comparisonType);static member StartsWith : ReadOnlySpan<char> * ReadOnlySpan<char> * StringComparison -> bool<Extension()>
Public Function StartsWith (span As ReadOnlySpan(Of Char), value As ReadOnlySpan(Of Char), comparisonType As StringComparison) As Boolean参数
- span
- ReadOnlySpan<Char>
源范围。
- value
- ReadOnlySpan<Char>
要与源范围的开头进行比较的序列。
- comparisonType
- StringComparison
一个枚举值，用于确定如何 span 比较和 value 比较。
返回
true 如果 value 与开头 span匹配，则为 ;否则为 false。
适用于
StartsWith<T>(ReadOnlySpan<T>, T, IEqualityComparer<T>)
- Source:
- MemoryExtensions.cs
- Source:
- MemoryExtensions.cs
确定指定值是否出现在范围开头。
public static bool StartsWith<T>(this ReadOnlySpan<T> span, T value, System.Collections.Generic.IEqualityComparer<T>? comparer = default);static member StartsWith : ReadOnlySpan<'T> * 'T * System.Collections.Generic.IEqualityComparer<'T> -> bool<Extension()>
Public Function StartsWith(Of T) (span As ReadOnlySpan(Of T), value As T, Optional comparer As IEqualityComparer(Of T) = Nothing) As Boolean类型参数
- T
范围中的元素类型。
参数
- span
- ReadOnlySpan<T>
要搜索的跨度。
- value
- T
要比较的值。
- comparer
- IEqualityComparer<T>
IEqualityComparer<T>比较元素时要使用的实现，或使用null元素类型的默认值IEqualityComparer<T>。
返回
true 如果 value 与开头 span匹配，则为 ;否则为 false。
适用于
StartsWith<T>(ReadOnlySpan<T>, ReadOnlySpan<T>, IEqualityComparer<T>)
- Source:
- MemoryExtensions.cs
- Source:
- MemoryExtensions.cs
确定指定的序列是否出现在只读范围开始时。
public static bool StartsWith<T>(this ReadOnlySpan<T> span, ReadOnlySpan<T> value, System.Collections.Generic.IEqualityComparer<T>? comparer = default);static member StartsWith : ReadOnlySpan<'T> * ReadOnlySpan<'T> * System.Collections.Generic.IEqualityComparer<'T> -> bool<Extension()>
Public Function StartsWith(Of T) (span As ReadOnlySpan(Of T), value As ReadOnlySpan(Of T), Optional comparer As IEqualityComparer(Of T) = Nothing) As Boolean类型参数
- T
参数
- span
- ReadOnlySpan<T>
源范围。
- value
- ReadOnlySpan<T>
要与开头进行比较的 span序列。
- comparer
- IEqualityComparer<T>
IEqualityComparer<T>比较元素时要使用的实现，或使用null元素类型的默认值IEqualityComparer<T>。
返回
适用于
StartsWith<T>(Span<T>, ReadOnlySpan<T>)
- Source:
- MemoryExtensions.cs
- Source:
- MemoryExtensions.cs
- Source:
- MemoryExtensions.cs
- Source:
- MemoryExtensions.cs
- Source:
- MemoryExtensions.cs
确定指定的序列是否出现在范围开头。
public:
generic <typename T>
where T : IEquatable<T>[System::Runtime::CompilerServices::Extension]
static bool StartsWith(Span<T> span, ReadOnlySpan<T> value);[System.Runtime.CompilerServices.OverloadResolutionPriority(-1)]
public static bool StartsWith<T>(this Span<T> span, ReadOnlySpan<T> value) where T : IEquatable<T>;public static bool StartsWith<T>(this Span<T> span, ReadOnlySpan<T> value) where T : IEquatable<T>;[<System.Runtime.CompilerServices.OverloadResolutionPriority(-1)>]
static member StartsWith : Span<'T (requires 'T :> IEquatable<'T>)> * ReadOnlySpan<'T (requires 'T :> IEquatable<'T>)> -> bool (requires 'T :> IEquatable<'T>)static member StartsWith : Span<'T (requires 'T :> IEquatable<'T>)> * ReadOnlySpan<'T (requires 'T :> IEquatable<'T>)> -> bool (requires 'T :> IEquatable<'T>)<Extension()>
Public Function StartsWith(Of T As IEquatable(Of T)) (span As Span(Of T), value As ReadOnlySpan(Of T)) As Boolean类型参数
- T
范围中元素的类型。
参数
- span
- Span<T>
要搜索的跨度。
- value
- ReadOnlySpan<T>
要在开头搜索的 span序列。
返回
true 如果 value 与开头 span匹配，则为 ;否则为 false。
- 属性
适用于
StartsWith<T>(ReadOnlySpan<T>, T)
- Source:
- MemoryExtensions.cs
- Source:
- MemoryExtensions.cs
- Source:
- MemoryExtensions.cs
确定指定值是否出现在范围开头。
public:
generic <typename T>
where T : IEquatable<T>[System::Runtime::CompilerServices::Extension]
static bool StartsWith(ReadOnlySpan<T> span, T value);public static bool StartsWith<T>(this ReadOnlySpan<T> span, T value) where T : IEquatable<T>;static member StartsWith : ReadOnlySpan<'T (requires 'T :> IEquatable<'T>)> * 'T -> bool (requires 'T :> IEquatable<'T>)<Extension()>
Public Function StartsWith(Of T As IEquatable(Of T)) (span As ReadOnlySpan(Of T), value As T) As Boolean类型参数
- T
范围中的元素类型。
参数
- span
- ReadOnlySpan<T>
要搜索的跨度。
- value
- T
要比较的值。
返回
true 如果 value 与开头 span匹配，则为 ;否则为 false。
适用于
StartsWith<T>(ReadOnlySpan<T>, ReadOnlySpan<T>)
- Source:
- MemoryExtensions.cs
- Source:
- MemoryExtensions.cs
- Source:
- MemoryExtensions.cs
- Source:
- MemoryExtensions.cs
- Source:
- MemoryExtensions.cs
确定指定的序列是否出现在只读范围开始时。
public:
generic <typename T>
where T : IEquatable<T>[System::Runtime::CompilerServices::Extension]
static bool StartsWith(ReadOnlySpan<T> span, ReadOnlySpan<T> value);public static bool StartsWith<T>(this ReadOnlySpan<T> span, ReadOnlySpan<T> value) where T : IEquatable<T>;static member StartsWith : ReadOnlySpan<'T (requires 'T :> IEquatable<'T>)> * ReadOnlySpan<'T (requires 'T :> IEquatable<'T>)> -> bool (requires 'T :> IEquatable<'T>)<Extension()>
Public Function StartsWith(Of T As IEquatable(Of T)) (span As ReadOnlySpan(Of T), value As ReadOnlySpan(Of T)) As Boolean类型参数
- T
范围中的元素类型。
参数
- span
- ReadOnlySpan<T>
要搜索的只读字符范围。
- value
- ReadOnlySpan<T>
要在开头搜索的 span序列。
返回
true 如果 value 与开头 span匹配，则为 ;否则为 false。
