Electronic Signature
Developers
Features
API for eSignature Solutions
Add text on a PDF document for eSignature with C# Client for API

Add text on a PDF document for eSignature with C# Client using the API

Instantly type and insert text anywhere on a PDF document using the airSlate SignNow API. Place text fields, adjust their size and insert any information that needs to be shared with other users.

Free to test
Fast to deploy
Powerful & secure

Share your comments and easily complement information on a PDF for recipients with added text.

Make discussions and understanding information in any document smooth and simple.

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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Get started with uninterrupted eSignature API: add text on a PDF document for eSignature with C# Client using the API

Consolidate and streamline your eSignature workflows and establish seamless processes. Try the airSlate SignNow API, implement eSignature workflows into your custom apps and websites in minutes, and seamlessly add text on a PDF document for eSignature with C# Client using the API.

Add text on a PDF document for eSignature with C# Client using the API the airSlate SignNow API for uninterrupted eSignature API

Click API on the airSlate 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 airSlate SignNow library.
When you're ready to go live, go to your airSlate 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 airSlate SignNow API is straightforward to embed, test, and operate (no sales people engaged). Gain the opportunity to add text on a PDF document for eSignature with C# Client using the API conveniently. Choose airSlate SignNow to get more optimized eSignature workflows.

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Copy required code from the library to add text on a PDF document for eSignature with C# Client using the API

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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.

The BEST Decision We Made

5

Laura H

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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Very good

5

Administrator

What do you like best?

It is user friendly and I cannot navigate the system very easily. The options of being able to copy the link and place it on another page allows me to use sign now very easily with other programs.

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5

Agency

What do you like best?

In own and operate a small business and this has been great in helping to close more business. I was printing out large amounts of paperwork for the client to sign before we could start helping them with their business. The problem was that the client felt overwhelmed and would delay in signing it until they took it home and read all the paperwork. Now that we have airSlate SignNow, they can look at it online and sign our agreement faster. Plus it saves time for me and my business trying to get this part complete. The customer is always looking for the easy button and this helps. We can also add this to our tabet setup so customers can sign up on the go with our team. Driving down operating costs while maintaining a high customer experience is what I strive for as a business owner and this provides the tools needed to grow.

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