--- title: "PdfFormFieldCollection" canonical_url: "https://www.nutrient.io/api/csharp/editors/pdf/formfields/pdf-form-field-collection/" md_url: "https://www.nutrient.io/api/csharp/editors/pdf/formfields/pdf-form-field-collection.md" last_updated: "2026-10-08T08:55:57.709Z" description: "Represents a collection of form fields in a PDF document. Provides access to the top-level form fields in the document's AcroForm." --- Represents a collection of form fields in a PDF document. Provides access to the top-level form fields in the document's AcroForm. ```csharp using Nutrient; ``` The SDK creates this class through factory methods or other SDK objects. ## Collection access `PdfFormFieldCollection` implements `IReadOnlyList`, so you can index it, read its `Count`, and iterate it with `foreach`. ```csharp public PdfFormField this[int index] { get; } ``` Gets the element at the specified 0-based index. **Type:** [`PdfFormField`](/api/csharp/editors/pdf/formfields/pdf-form-field/) ## Properties ### Count ```csharp public int Count { get; } ``` The number of top-level form fields in the document. **Type:** `int` ## Methods ### AddCheckBoxField ```csharp public PdfCheckBoxField AddCheckBoxField(string name, PdfPage page, float x, float y, float width, float height) ``` Adds a new check box field to the document on the specified page. **Parameters** | Name | Type | Description | | -------- | ---------------------------------------------------- | -------------------------------------------------------------------- | | `name` | `string` | The name of the check box field. Must be unique within the document. | | `page` | [`PdfPage`](/api/csharp/editors/pdf/pages/pdf-page/) | The page where the check box field will be placed. | | `x` | `float` | The x coordinate of the field's origin in points. | | `y` | `float` | The y coordinate of the field's origin in points. | | `width` | `float` | The width of the field in points. | | `height` | `float` | The height of the field in points. | **Returns:** [`PdfCheckBoxField`](/api/csharp/editors/pdf/formfields/pdf-check-box-field/) - The newly created `PdfCheckBoxField`. **Throws:** [`NutrientException`](/api/csharp/exceptions/nutrient-exception/) - Thrown when no document is loaded. **Throws:** [`NutrientException`](/api/csharp/exceptions/nutrient-exception/) - Thrown when the field creation fails. ### AddComboBoxField ```csharp public PdfComboBoxField AddComboBoxField(string name, PdfPage page, float x, float y, float width, float height) ``` Adds a new combo box (drop-down list) field to the document on the specified page. **Parameters** | Name | Type | Description | | -------- | ---------------------------------------------------- | -------------------------------------------------------------------- | | `name` | `string` | The name of the combo box field. Must be unique within the document. | | `page` | [`PdfPage`](/api/csharp/editors/pdf/pages/pdf-page/) | The page where the combo box field will be placed. | | `x` | `float` | The x coordinate of the field's origin in points. | | `y` | `float` | The y coordinate of the field's origin in points. | | `width` | `float` | The width of the field in points. | | `height` | `float` | The height of the field in points. | **Returns:** [`PdfComboBoxField`](/api/csharp/editors/pdf/formfields/pdf-combo-box-field/) - The newly created `PdfComboBoxField`. **Throws:** [`NutrientException`](/api/csharp/exceptions/nutrient-exception/) - Thrown when no document is loaded. **Throws:** [`NutrientException`](/api/csharp/exceptions/nutrient-exception/) - Thrown when the field creation fails. ### AddListBoxField ```csharp public PdfListBoxField AddListBoxField(string name, PdfPage page, float x, float y, float width, float height) ``` Adds a new list box field to the document on the specified page. **Parameters** | Name | Type | Description | | -------- | ---------------------------------------------------- | ------------------------------------------------------------------- | | `name` | `string` | The name of the list box field. Must be unique within the document. | | `page` | [`PdfPage`](/api/csharp/editors/pdf/pages/pdf-page/) | The page where the list box field will be placed. | | `x` | `float` | The x coordinate of the field's origin in points. | | `y` | `float` | The y coordinate of the field's origin in points. | | `width` | `float` | The width of the field in points. | | `height` | `float` | The height of the field in points. | **Returns:** [`PdfListBoxField`](/api/csharp/editors/pdf/formfields/pdf-list-box-field/) - The newly created `PdfListBoxField`. **Throws:** [`NutrientException`](/api/csharp/exceptions/nutrient-exception/) - Thrown when no document is loaded. **Throws:** [`NutrientException`](/api/csharp/exceptions/nutrient-exception/) - Thrown when the field creation fails. ### AddPushButtonField ```csharp public PdfPushButtonField AddPushButtonField(string name, PdfPage page, float x, float y, float width, float height) ``` Adds a new push button field to the document on the specified page. **Parameters** | Name | Type | Description | | -------- | ---------------------------------------------------- | ---------------------------------------------------------------------- | | `name` | `string` | The name of the push button field. Must be unique within the document. | | `page` | [`PdfPage`](/api/csharp/editors/pdf/pages/pdf-page/) | The page where the push button field will be placed. | | `x` | `float` | The x coordinate of the field's origin in points. | | `y` | `float` | The y coordinate of the field's origin in points. | | `width` | `float` | The width of the field in points. | | `height` | `float` | The height of the field in points. | **Returns:** [`PdfPushButtonField`](/api/csharp/editors/pdf/formfields/pdf-push-button-field/) - The newly created `PdfPushButtonField`. **Throws:** [`NutrientException`](/api/csharp/exceptions/nutrient-exception/) - Thrown when no document is loaded. **Throws:** [`NutrientException`](/api/csharp/exceptions/nutrient-exception/) - Thrown when the field creation fails. ### AddRadioButtonField ```csharp public PdfRadioButtonField AddRadioButtonField(string groupName, string optionName, PdfPage page, float x, float y, float width, float height) ``` Adds a new radio button to an existing or new radio button group on the specified page. **Parameters** | Name | Type | Description | | ------------ | ---------------------------------------------------- | ------------------------------------------------------------------------------------------------------ | | `groupName` | `string` | The name of the radio button group. All radio buttons with the same group name are mutually exclusive. | | `optionName` | `string` | The unique option name for this radio button within the group. | | `page` | [`PdfPage`](/api/csharp/editors/pdf/pages/pdf-page/) | The page where the radio button will be placed. | | `x` | `float` | The x coordinate of the field's origin in points. | | `y` | `float` | The y coordinate of the field's origin in points. | | `width` | `float` | The width of the field in points. | | `height` | `float` | The height of the field in points. | **Returns:** [`PdfRadioButtonField`](/api/csharp/editors/pdf/formfields/pdf-radio-button-field/) - The `PdfRadioButtonField` representing the radio button group. **Throws:** [`NutrientException`](/api/csharp/exceptions/nutrient-exception/) - Thrown when no document is loaded. **Throws:** [`NutrientException`](/api/csharp/exceptions/nutrient-exception/) - Thrown when the field creation fails. ### AddSignatureField ```csharp public PdfSignatureField AddSignatureField(string name, PdfPage page, float x, float y, float width, float height) ``` Adds a new signature field to the document on the specified page. **Parameters** | Name | Type | Description | | -------- | ---------------------------------------------------- | -------------------------------------------------------------------- | | `name` | `string` | The name of the signature field. Must be unique within the document. | | `page` | [`PdfPage`](/api/csharp/editors/pdf/pages/pdf-page/) | The page where the signature field will be placed. | | `x` | `float` | The x coordinate of the field's origin in points. | | `y` | `float` | The y coordinate of the field's origin in points. | | `width` | `float` | The width of the field in points. | | `height` | `float` | The height of the field in points. | **Returns:** [`PdfSignatureField`](/api/csharp/editors/pdf/formfields/pdf-signature-field/) - The newly created `PdfSignatureField`. **Throws:** [`NutrientException`](/api/csharp/exceptions/nutrient-exception/) - Thrown when no document is loaded. **Throws:** [`NutrientException`](/api/csharp/exceptions/nutrient-exception/) - Thrown when the field creation fails. ### AddTextField ```csharp public PdfTextField AddTextField(string name, PdfPage page, float x, float y, float width, float height) ``` Adds a new text field to the document on the specified page. **Parameters** | Name | Type | Description | | -------- | ---------------------------------------------------- | --------------------------------------------------------------- | | `name` | `string` | The name of the text field. Must be unique within the document. | | `page` | [`PdfPage`](/api/csharp/editors/pdf/pages/pdf-page/) | The page where the text field will be placed. | | `x` | `float` | The x coordinate of the field's origin in points. | | `y` | `float` | The y coordinate of the field's origin in points. | | `width` | `float` | The width of the field in points. | | `height` | `float` | The height of the field in points. | **Returns:** [`PdfTextField`](/api/csharp/editors/pdf/formfields/pdf-text-field/) - The newly created `PdfTextField`. **Throws:** [`NutrientException`](/api/csharp/exceptions/nutrient-exception/) - Thrown when no document is loaded. **Throws:** [`NutrientException`](/api/csharp/exceptions/nutrient-exception/) - Thrown when the field creation fails. ### Clear ```csharp public void Clear() ``` Removes all form fields from the document. **Throws:** [`NutrientException`](/api/csharp/exceptions/nutrient-exception/) - Thrown when no document is loaded. **Throws:** [`NutrientException`](/api/csharp/exceptions/nutrient-exception/) - Thrown when the operation fails. ### FindByFullName ```csharp public PdfFormField? FindByFullName(string fullName) ``` Finds a form field by its full name (dot-separated path). **Parameters** | Name | Type | Description | | ---------- | -------- | -------------------------------------- | | `fullName` | `string` | The fully qualified name of the field. | **Returns:** [`PdfFormField`](/api/csharp/editors/pdf/formfields/pdf-form-field/) or `null` - The `PdfFormField` if found, null otherwise. ### RemoveAt ```csharp public void RemoveAt(int index) ``` Removes the form field at the specified index. This also removes any child fields and associated widget annotations. **Parameters** | Name | Type | Description | | ------- | ----- | ----------------------------------------- | | `index` | `int` | The 0-based index of the field to remove. | **Throws:** [`NutrientException`](/api/csharp/exceptions/nutrient-exception/) - Thrown when index is out of range. **Throws:** [`NutrientException`](/api/csharp/exceptions/nutrient-exception/) - Thrown when the operation fails. ## Resource management ```csharp public void Dispose() ``` `PdfFormFieldCollection` implements `IDisposable`. Call `Dispose()` or use a C# `using` declaration to release its native handle right away. If you don't, the handle is released when the object is garbage collected. --- ## Related pages - [Formfields](/api/csharp/editors/pdf/formfields.md) - [Pdf Check Box Field](/api/csharp/editors/pdf/formfields/pdf-check-box-field.md) - [Pdf Combo Box Field](/api/csharp/editors/pdf/formfields/pdf-combo-box-field.md) - [Pdf Form Field](/api/csharp/editors/pdf/formfields/pdf-form-field.md) - [Pdf List Box Field](/api/csharp/editors/pdf/formfields/pdf-list-box-field.md) - [Pdf Push Button Field](/api/csharp/editors/pdf/formfields/pdf-push-button-field.md) - [Pdf Radio Button Field](/api/csharp/editors/pdf/formfields/pdf-radio-button-field.md) - [Pdf Signature Field](/api/csharp/editors/pdf/formfields/pdf-signature-field.md) - [Pdf Text Field](/api/csharp/editors/pdf/formfields/pdf-text-field.md)