Electronic Signature
Developers
Features
API for eSignature Solutions
Write text on a PDF document for eSignature using API

Write text on a PDF document for eSignature using API

Write anything you want on a PDF document using the airSlate SignNow API. Put a text field next to the information you need to complement and share text with your recipients after sending.

Free to test
Fast to deploy
Powerful & secure

Edit PDFs by writing text anywhere on a document.

Adjust the text to fit your needs by fixing its size and location in a document.

C#

Java

Copy code

public class ResponseDocumentFieldsModel
    {
        public ResponseDocumentField[] fields { get; set; }
        public object[] signatures { get; set; }
        public object[] texts { get; set; }
        public object[] checks { get; set; }
        public object[] radiobuttons { get; set; }
        public object[] attachments { get; set; }
        public Enumeration_Options[] enumeration_options { get; set; }
    }

public class Enumeration_Options
    {
        public string id { get; set; }
        public string enumeration_id { get; set; }
        public string data { get; set; }
        public string created { get; set; }
        public string updated { get; set; }
        public string json_attributes { get; set; }
    }
    public class ResponseDocumentField
    {
        public string id { get; set; }
        public string type { get; set; }
        public string role_id { get; set; }
        public ResponseJson_Attributes json_attributes { get; set; }
        public string role { get; set; }
        public string originator { get; set; }
        public string fulfiller { get; set; }
        public string field_request_id { get; set; }
        public string element_id { get; set; }
        public object field_request_canceled { get; set; }
        public string template_field_id { get; set; }
        public string field_id { get; set; }
        public Radio[] radio { get; set; }
    }
    public class ResponseJson_Attributes
    {
        public int page_number { get; set; }
        public int x { get; set; }
        public int y { get; set; }
        public int width { get; set; }
        public int height { get; set; }
        public bool required { get; set; }
        public string label { get; set; }
        public object prefilled_text { get; set; }
        public string custom_defined_option { get; set; }
        public string name { get; set; }
        public dynamic calculation_formula { get; set; }
        public string formula { get; set; }
        public bool italic { get; set; }
        public bool bold { get; set; }
        public int calculation_precision { get; set; }
        public string validator_id { get; set; }
        public int size { get; set; }
        public string font { get; set; }
        public int line_height { get; set; }
    }
    public class RequestUpdateFieldValueModel
    {
        public object[] texts { get; set; }
        public object[] signatures { get; set; }
        public object[] checks { get; set; }
        public object[] radiobuttons { get; set; }
        public object[] attachments { get; set; }
        public List<RequestFieldModel> fields { get; set; }
        public int client_timestamp { get; set; }
    }
    public class RequestFieldModel
    {
        public int page_number { get; set; }
        public string role { get; set; }
        public string type { get; set; }
        public string name { get; set; }
        public bool required { get; set; }
        public int width { get; set; }
        public int height { get; set; }
        public int x { get; set; }
        public int y { get; set; }
        public object prefilled_text { get; set; }
        public string label { get; set; }
        public bool bold { get; set; }
        public bool underline { get; set; }
        public string align { get; set; }
        public string valign { get; set; }
        public string arrangement { get; set; }
        public int max_chars { get; set; }
        public int max_lines { get; set; }
        public string font { get; set; }
        public int size { get; set; }
        public bool custom_defined_option { get; set; }
        [JsonProperty(NullValueHandling = NullValueHandling.Ignore)]
        public Radio[] radio { get; set; }
        [JsonProperty(NullValueHandling = NullValueHandling.Ignore)]
        public IEnumerable<string> enumeration_options { get; set; }
        public object calculation_formula { get; set; }
        [JsonProperty(NullValueHandling = NullValueHandling.Ignore)]
        public int calculation_precision { get; set; }
        [JsonProperty(NullValueHandling = NullValueHandling.Ignore)]
        public bool italic { get; set; }
        [JsonProperty(NullValueHandling = NullValueHandling.Ignore)]
        public string formula { get; set; }
        [JsonProperty(NullValueHandling = NullValueHandling.Ignore)]
        public float line_height { get; set; }
    }
public partial class RestSharpSamples
    {
        /// <summary>
        /// Get Set prefilled values based on field unique name.
        /// </summary>
        public static void SetTemplateInitialValues(string accessToken, string apiUrl, string templateId, Dictionary<string,object> fieldValue)
        {
            if (!fieldValue.Any())
            {
                return;
            }
            var client = new RestClient { BaseUrl = new Uri(apiUrl) };

var request = new RestRequest($"/document/{templateId}", Method.GET)
                .AddHeader("Accept", "application/json")
                .AddHeader("Authorization", $"Bearer {accessToken}");

var response = client.Execute(request);

if (response.StatusCode != HttpStatusCode.OK)
            {
                throw new Exception(response.Content);
            }
            var documentResponse = JsonConvert.DeserializeObject<ResponseDocumentFieldsModel>(response.Content);
            var fieldUpdateRequest = new List<RequestFieldModel>();
            foreach (var field in documentResponse.fields)
            {
                var foundField = fieldValue.FirstOrDefault(e => e.Key.Equals(field.json_attributes.name));
                if (foundField.Value != null)
                {
                    field.json_attributes.prefilled_text = foundField.Value;
                }

var customDefValue = field.json_attributes.custom_defined_option == "1" ? true : false;

var fieldModel = new RequestFieldModel
                {
                    height = field.json_attributes.height,
                    label = field.json_attributes.label,
                    name = field.json_attributes.name,
                    page_number = field.json_attributes.page_number,
                    prefilled_text = field.json_attributes.prefilled_text,
                    required = field.json_attributes.required,
                    role = field.role,
                    width = field.json_attributes.width,
                    x = field.json_attributes.x,
                    y = field.json_attributes.y,
                    font = field.json_attributes.font,
                    formula = field.json_attributes.formula,
                    bold = field.json_attributes.bold,
                    calculation_formula = field.json_attributes.calculation_formula,
                    calculation_precision = field.json_attributes.calculation_precision,
                    italic = field.json_attributes.italic,
                    line_height = field.json_attributes.line_height,
                    custom_defined_option = customDefValue,
                    type = field.type,
                    size = field.json_attributes.size,
                    radio = field.radio                   
                };
                if (field.type == "enumeration")
                {
                    fieldModel.enumeration_options = documentResponse.enumeration_options.Where(e => e.id == field.id).Select(e => e.data);
                }
                fieldUpdateRequest.Add(fieldModel);
            }

var updateField = new RequestUpdateFieldValueModel {
                checks = documentResponse.checks,
                attachments = documentResponse.attachments,
                radiobuttons = documentResponse.radiobuttons,
                signatures = documentResponse.signatures,
                texts = documentResponse.texts,
                fields = fieldUpdateRequest
            };

var documentUpdateRequest = new RestRequest($"/document/{templateId}", Method.PUT)
                .AddHeader("Accept", "application/json")
                .AddHeader("Authorization", $"Bearer {accessToken}");

documentUpdateRequest.RequestFormat = DataFormat.Json;
            documentUpdateRequest.AddBody(updateField);

var updateResponse = client.Execute(documentUpdateRequest);
            if (response.StatusCode != HttpStatusCode.OK)
            {
                throw new Exception("Updating field values failed: " + updateResponse.Content);
            }
        }
    }
}

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Use code samples to write text on a PDF document for eSignature using API

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