Electronic Signature
Developers
Features
API for eSignature Solutions
Automatically fill out forms for signing using cURL

Automatically fill out forms for signing using cURL

Add data to fillable forms using the signNow API. Prefill date, text, and initials fields right from your app or website on any device, without the need to manually type data. You can then download a completed PDF or send it for signing in seconds.

Free to test
Fast to deploy
Powerful & secure

Easily fill out forms using the signNow API

Automatically insert data into the smart fields of your fillable document using signNow code samples.

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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Watch the signNow API in action

Get started with uninterrupted eSignature API: automatically fill out forms for signing using cURL

Consolidate and streamline your eSignature workflows and establish seamless processes. Try the signNow API, implement eSignature workflows into your custom apps and websites in minutes, and seamlessly automatically fill out forms for signing using cURL.

Automatically fill out forms for signing using cURL the signNow API for uninterrupted eSignature API

Click API on the signNow main page and create your API Sandbox account.
Open your email to confirm the registration and specify a password for accessing your Developer Sandbox environment.
Find the list of your apps at the top of the page. By default, you can also find a Test App for testing the API.
Click its name to access the Client ID and Basic Authorization Token.
Launch the API using the information from the previous step.
Use the code samples from the signNow library.
When you're ready to go live, go to your signNow account and choose a subscription plan.
If you can't find a subscription that suits your needs, contact the Sales team.
Change the test URL in your requests to the production environment URL.
Delight your customers and partners with a streamlined eSignature experience.

The signNow API is straightforward to embed, test, and work with (no vendor involved). Get the capability to automatically fill out forms for signing using cURL easily. Choose signNow for more streamlined eSignature workflows.

How it works

Create an account and get the required tokens

Use code samples to automatically fill out forms for signing using cURL

Enjoy the power of eSignature in your workflows

Watch our instructions to build custom integrations with ease

signNow offers a free testing environment to explore the eSignature.

Trusted eSignature solution — what our customers are saying

Explore how the signNow eSignature platform helps businesses succeed. Hear from real users and what they like most about electronic signing.

The BEST Decision We Made

5

Laura Hardin

What do you like best?

We were previously using an all-paper hiring and on-boarding method. We switched all those documents over to Sign Now, and our whole process is so much easier and smoother. We have 7 terminals in 3 states so being all-paper was cumbersome and, frankly, silly. We've removed so much of the burden from our terminal managers so they can do what they do: manage the business.

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Excellent platform, is useful and intuitive.

5

Renato Cirelli

What do you like best?

It is innovative to send documents to customers and obtain your signatures and to notify customers when documents are signed and the process is simple for them to do so. SignNow is a configurable digital signature tool.

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Easy to use, increases productivity

5

Erin Jones

What do you like best?

I love that I can complete signatures and documents from the phone app in addition to using my desktop. As a busy administrator, this speeds up productivity . I find the interface very easy and clear, a big win for our office. We have improved engagement with our families , and increased dramatically the amount of crucial signatures needed for our program. I have not heard any complaints that the interface is difficult or confusing, instead have heard feedback that it is easy to use. Most importantly is the ability to sign on mobile phone, this has been a game changer for us.

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