# Hyperlink
```csharp
public sealed class Hyperlink
```
Namespace `SharpCell` ยท package `SharpCell`
A hyperlink on a cell: a web or e-mail address, a file, or a place in the workbook. The cell's value is what Excel shows; the link neither changes it nor applies the Hyperlink cell style.
## Constructors
### Hyperlink(string, string)
```csharp
public Hyperlink(string target, string? tooltip = null)
```
A link to `target`, with an optional tooltip.
**Parameters**
- `target`: A web or e-mail address or a file (`https://example.com`, `mailto:a@example.com`, `report.pdf`), or a place in the workbook written as Excel's HYPERLINK function takes it: `#Sheet2!A1`, `#'Q1 Sales'!A1` or `#MyName`.
- `tooltip`: Excel's ScreenTip, shown when the pointer rests on the cell; at most 255 characters, or null for none.
**Exceptions**
- `ArgumentNullException`: The target is null.
- `ArgumentException`: The target is empty or only `#`, or the tooltip is longer than 255 characters.
## Properties
### IsInWorkbook
```csharp
public bool IsInWorkbook { get; }
```
Whether the link goes to a place in this workbook, that is, the target starts with `#`.
### Target
```csharp
public string Target { get; }
```
Where the link goes, as given to the constructor.
An empty fragment is dropped when the link is saved: `https://example.com/#` reads back as `https://example.com/`.
### Tooltip
```csharp
public string? Tooltip { get; }
```
The ScreenTip, or null for none.
## Methods
### Equals(Hyperlink)
```csharp
public bool Equals(Hyperlink? other)
```
Whether the other link has the same target and tooltip, compared ordinally.
### Equals(object)
```csharp
public override bool Equals(object? obj)
```
Whether `obj` is the same link.
### GetHashCode()
```csharp
public override int GetHashCode()
```
A hash code consistent with [Hyperlink.Equals](SharpCell.Hyperlink.md#equals-hyperlink).
### ToString()
```csharp
public override string ToString()
```
The target.