Electronic Signature
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Features
API for eSignature Solutions
Automatically fill out forms for signing with C# Client for API

Automatically fill out forms for signing with C# Client using the API

Add data to fillable forms using the airSlate 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 airSlate SignNow API

Automatically insert data into the smart fields of your fillable document using airSlate 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);
            }
        }
    }
}

We provide developers with complete SDKs for all popular languages, allowing them to integrate eSignature workflows without writing a single line of code.
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The airSlate SignNow API not only provides you with eSignatures: use it to create fillable forms, request payments, and download & archive documents using simple API calls.

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Watch the airSlate SignNow API in action

Evaluate airSlate SignNow's automatically fill out forms with c client for api

The airSlate SignNow API provides organizations with a distinctive array of features that facilitate more effective business operations. Discover the benefits of our automatically fill out forms with c client for api by using a complimentary Sandbox account.

Complete these instructions to establish a Sandbox account:

Navigate to the airSlate SignNow Developers page. There, you can find additional details regarding the API and register for your Sandbox account.
Register for a trial. Enter your email address and click the Create API sandbox button to sign up.
Verify your email address. Access the email you receive and follow the link to verify your email address.
Access Developer Sandbox. Create a password to facilitate further entry into your developer account.
Include an application. Click Add App, designate a name for your app, and click Add to save changes. The API token for the application will be generated automatically.
Examine automatically fill out forms with c client for api. Delve into all the airSlate SignNow features and how they can improve your business functions.

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How it works

Create an account and get the required tokens

Use code samples to automatically fill out forms for signing with C# Client using the API

Enjoy the power of eSignature in your workflows

Watch our instructions to build custom integrations with ease

airSlate SignNow offers a free testing environment to explore the eSignature.

Trusted eSignature solution — what our customers are saying

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

I've been using airSlate SignNow for years (since it...

5

Susan S

I've been using airSlate SignNow for years (since it was CudaSign). I started using airSlate SignNow for real estate as it was easier for my clients to use. I now use it in my business for employement and onboarding docs.

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Everything has been great, really easy to incorporate...

5

Liam R

Everything has been great, really easy to incorporate into my business. And the clients who have used your software so far have said it is very easy to complete the necessary signatures.

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I couldn't conduct my business without contracts and...

5

Dani P

I couldn't conduct my business without contracts and this makes the hassle of downloading, printing, scanning, and reuploading docs virtually seamless. I don't have to worry about whether or not my clients have printers or scanners and I don't have to pay the ridiculous drop box fees. Sign now is amazing!!

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