Electronic Signature
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API for eSignature Solutions
Add text on a PDF document for eSignature with C# SDK for API

Add text on a PDF document for eSignature with C# SDK 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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Use code samples to add text on a PDF document for eSignature with C# SDK using the API

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Ease of getting our contracts signed from customers.

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Before using airSlate SignNow, I had worked with one other eSign program, so I am no expert by any means. What I liked best about airSlate SignNow, is it was very easy to jump right into using. We are a small business and primarily use it to have new sales partners sign their agreements, payment schedules, etc. It was easy to add a combined agreement and insert text, date, and signature fields. I also like that it provides a link and an embed code depending on your version you purchase.

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The ease of this product makes business streamline easier. We are able to have clients who are tech savvy and not so tech savvy use the program.

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