# Using a String Comparison Validator

Learn how to create a string comparison validator and display an error icon with a text tip using the CompareStringValidator class in Spread.NET.

## Content

You can create a validator that compares string values.
A validation error occurs if the value does not match the specified conditions. You can also create an action, such as displaying an icon in the cell, that lets the user know the value is invalid.
Use the **CompareStringValidator** class to create the string validator. Specify a notification type such as [IconNotify](/spreadnet/api/latest/online-win/FarPoint.Win.Spread/FarPoint.Win.Spread.IconNotify.html). Then use the [AddValidators](/spreadnet/api/latest/online-win/FarPoint.Win.Spread/FarPoint.Win.Spread.SheetView.AddValidators.html) method to add the validator to a cell range.
The following image displays an error icon with a text tip.
![String Comparision Validator](https://cdn.mescius.io/document-site-files/images/2238e618-a1fb-45a6-9ce5-9a4157bd2931/images/iconnotify.png)

## Using Code

The following example displays an icon if you type a string that does not contain "Test".

```csharp
//Type a value in cell 1,1
FarPoint.Win.Spread.IconNotify iconn = new FarPoint.Win.Spread.IconNotify();
iconn.Icon = new System.Drawing.Icon("C:\\Program Files (x86)\\Mescius\\spread.ico");
iconn.IconAlignment = ContentAlignment.MiddleCenter;
iconn.IconTip = "Must contain Test";
FarPoint.Win.Spread.CompareStringValidator svalid = new FarPoint.Win.Spread.CompareStringValidator();
svalid.ComparedOperator = FarPoint.Win.Spread.CompareStringValidatorOperator.Contains;
svalid.ComparedString = "Test";
svalid.Actions.Add(iconn);
fpSpread1.Sheets[0].AddValidators(new FarPoint.Win.Spread.Model.CellRange(1, 1, 1, 1), svalid);
fpSpread1.Sheets[0].Columns[1].Width = 140;
fpSpread1.Sheets[0].Rows[1].Height = 50;
```

```vbnet
'Type a value in cell 1,1
Dim iconn As New FarPoint.Win.Spread.IconNotify()
iconn.Icon = New System.Drawing.Icon("C:\Program Files (x86)\Mescius\spread.ico")
iconn.IconAlignment = ContentAlignment.MiddleCenter
iconn.IconTip = "Must contain Test"
Dim svalid As New FarPoint.Win.Spread.CompareStringValidator()
svalid.ComparedOperator = FarPoint.Win.Spread.CompareStringValidatorOperator.Contains
svalid.ComparedString = "Test"
svalid.Actions.Add(iconn)
fpSpread1.Sheets(0).AddValidators(New FarPoint.Win.Spread.Model.CellRange(1, 1, 1, 1), svalid)
fpSpread1.Sheets(0).Columns(1).Width = 140
fpSpread1.Sheets(0).Rows(1).Height = 50
```

## See Also

[Using a Cell Comparison Validator](/spreadnet/docs/latest/online-win/overview/spwin-devguide/spwin-interactcell/spwin-cellvalid/spwin-cellvalidation/spwin-cellcomparevalidator)
[Using a Character Format Validator](/spreadnet/docs/latest/online-win/overview/spwin-devguide/spwin-interactcell/spwin-cellvalid/spwin-cellvalidation/spwin-cellcharformatv)
[Using a Value Comparison Validator](/spreadnet/docs/latest/online-win/overview/spwin-devguide/spwin-interactcell/spwin-cellvalid/spwin-cellvalidation/spwin-cellcomparevalue)
[Using an Encoding Validator](/spreadnet/docs/latest/online-win/overview/spwin-devguide/spwin-interactcell/spwin-cellvalid/spwin-cellvalidation/spwin-cellencodingvalid)
[Using the Exclude List Validator](/spreadnet/docs/latest/online-win/overview/spwin-devguide/spwin-interactcell/spwin-cellvalid/spwin-cellvalidation/spwin-cellexcludevalidator)
[Using the Include List Validator](/spreadnet/docs/latest/online-win/overview/spwin-devguide/spwin-interactcell/spwin-cellvalid/spwin-cellvalidation/spwin-cellincludevalidate)
[Using a Pair Validator](/spreadnet/docs/latest/online-win/overview/spwin-devguide/spwin-interactcell/spwin-cellvalid/spwin-cellvalidation/spwin-cellpairvalidate)
[Using the Range Validator](/spreadnet/docs/latest/online-win/overview/spwin-devguide/spwin-interactcell/spwin-cellvalid/spwin-cellvalidation/spwin-cellrangevalidator)
[Using a Regular Expression Validator](/spreadnet/docs/latest/online-win/overview/spwin-devguide/spwin-interactcell/spwin-cellvalid/spwin-cellvalidation/spwin-cellregexpression)
[Using a Required Field Validator](/spreadnet/docs/latest/online-win/overview/spwin-devguide/spwin-interactcell/spwin-cellvalid/spwin-cellvalidation/spwin-cellrequiredvalid)
[Using a Required Type Validator](/spreadnet/docs/latest/online-win/overview/spwin-devguide/spwin-interactcell/spwin-cellvalid/spwin-cellvalidation/spwin-cellrequiretypev)
[Using a Surrogate Character Validator](/spreadnet/docs/latest/online-win/overview/spwin-devguide/spwin-interactcell/spwin-cellvalid/spwin-cellvalidation/spwin-cellsurrogate)
[Using a Text Length Validator](/spreadnet/docs/latest/online-win/overview/spwin-devguide/spwin-interactcell/spwin-cellvalid/spwin-cellvalidation/spwin-celltextlvalid)