Electronic Signature
Developers
Features
API for eSignature Solutions
Send a document for signing and request attachments with C# SDK for API

Send a document for signing and request attachments with C# SDK using the API

Use signNow’s API to ensure data collected from your customers is 100% complete. Create and send an attachment request for one or several additional documents required to complete your workflow.

Free to test
Fast to deploy
Powerful & secure

Request additional documents from signers

Use the sample code to make a request for documents to be added to an existing eSignature workflow.

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public class DocumentUpdateRequestModel
    {
        public List<FieldRequestBase> fields { get; private set; } = new List<FieldRequestBase>();
    }
 
    public abstract class FieldRequestBase
    {
        public abstract string type { get; }
        public bool required { get; set; }
        public string template_field_id { get; set; }
        public string role { get; set; }
        [JsonProperty(NullValueHandling = NullValueHandling.Ignore)]
        public string name { get; set; }
        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 abstract class LabelledFieldRequest : FieldRequestBase
    {
        public string label { get; set; }
    }
 
    public abstract class TextFieldRequestBase : LabelledFieldRequest
    {
        public override string type => "text";
 
    }
    public class TextFieldRequest : TextFieldRequestBase
    {
        public string prefilled_text { get; set; }
        public string validator_id { get; set; }
    }
    public class InitialsFieldRequest : LabelledFieldRequest
    {
        public override string type { get { return "initials"; } }
    }
    public class CheckboxFieldRequestModel : LabelledFieldRequest
    {
        public override string type => "checkbox";
        public bool prefilled_text { get; set; }
    }
 
    public class DropdownFieldRequest : LabelledFieldRequest
    {
        public override string type => "enumeration";
        public string[] enumeration_options { get; set; }
        public bool custom_defined_option { get; set; }
    }
 
    public class CalculatedFieldRequest : TextFieldRequestBase
    {
        /// <summary>
        /// Formula that includes field names and operations
        /// </summary>
        public Formula calculation_formula { get; set; }
        /// <summary>
        /// String representation of the formula. Just a text that user will see in the field settings.
        /// </summary>
        public string formula { get; set; }
        public int calculation_precision { get; set; }
    }
 
    public enum FormulaOperator
    {
        add, sub, div, mul
    }
 
    public class Formula
    {
        [JsonProperty(NullValueHandling = NullValueHandling.Ignore)]
        [JsonConverter(typeof(StringEnumConverter))]
        public FormulaOperator? @operator { get; private set; }
        [JsonProperty(NullValueHandling = NullValueHandling.Ignore)]
        public object term { get; private set; }
        [JsonProperty(NullValueHandling = NullValueHandling.Ignore)]
        public Formula left { get; private set; }
        [JsonProperty(NullValueHandling = NullValueHandling.Ignore)]
        public Formula right { get; private set; }
        private Formula(object term)
        {
            this.term = term;
        }
        private Formula(FormulaOperator @operator, Formula leftOperand, Formula rightOperand)
        {
            this.@operator = @operator;
            left = leftOperand;
            right = rightOperand;
        }
        private Formula(FormulaOperator @operator, string leftFieldName, string rightFieldName)
            : this(@operator, new Formula(leftFieldName), new Formula(rightFieldName))
        {
        }
        private Formula(FormulaOperator @operator, string leftFieldName, Formula rightOperand)
            : this(@operator, new Formula(leftFieldName), rightOperand)
        {
        }
        private Formula(FormulaOperator @operator, Formula leftOperand, string rightFieldName)
            : this(@operator, leftOperand, new Formula(rightFieldName))
        {
        }
        public static Formula Add(string leftFieldName, string rightFieldName)
        {
            return new Formula(FormulaOperator.add, leftFieldName, rightFieldName);
        }
        public static Formula Add(string leftFieldName, Formula rightOperand)
        {
            return new Formula(FormulaOperator.add, leftFieldName, new Formula(rightOperand));
        }
        public static Formula Add(Formula leftOperand, string rightFieldName)
        {
            return new Formula(FormulaOperator.add, new Formula(leftOperand), rightFieldName);
        }
        public static Formula Add(Formula leftOperand, Formula rightOperand)
        {
            return new Formula(FormulaOperator.add, new Formula(leftOperand), new Formula(rightOperand));
        }
        public static Formula Sub(string leftFieldName, string rightFieldName)
        {
            return new Formula(FormulaOperator.sub, leftFieldName, rightFieldName);
        }
        public static Formula Sub(string leftFieldName, Formula rightOperand)
        {
            return new Formula(FormulaOperator.sub, leftFieldName, new Formula(rightOperand));
        }
        public static Formula Sub(Formula leftOperand, string rightFieldName)
        {
            return new Formula(FormulaOperator.sub, new Formula(leftOperand), rightFieldName);
        }
        public static Formula Sub(Formula leftOperand, Formula rightOperand)
        {
            return new Formula(FormulaOperator.sub, new Formula(leftOperand), new Formula(rightOperand));
        }
        public static Formula Mul(string leftFieldName, string rightFieldName)
        {
            return new Formula(FormulaOperator.mul, leftFieldName, rightFieldName);
        }
        public static Formula Mul(string leftFieldName, Formula rightOperand)
        {
            return new Formula(FormulaOperator.mul, leftFieldName, new Formula(rightOperand));
        }
        public static Formula Mul(Formula leftOperand, string rightFieldName)
        {
            return new Formula(FormulaOperator.mul, new Formula(leftOperand), rightFieldName);
        }
        public static Formula Mul(Formula leftOperand, Formula rightOperand)
        {
            return new Formula(FormulaOperator.mul, new Formula(leftOperand), new Formula(rightOperand));
        }
        public static Formula Div(string leftFieldName, string rightFieldName)
        {
            return new Formula(FormulaOperator.div, leftFieldName, rightFieldName);
        }
        public static Formula Div(string leftFieldName, Formula rightOperand)
        {
            return new Formula(FormulaOperator.div, leftFieldName, new Formula(rightOperand));
        }
        public static Formula Div(Formula leftOperand, string rightFieldName)
        {
            return new Formula(FormulaOperator.div, new Formula(leftOperand), rightFieldName);
        }
        public static Formula Div(Formula leftOperand, Formula rightOperand)
        {
            return new Formula(FormulaOperator.div, new Formula(leftOperand), new Formula(rightOperand));
        }
    }
 
    public class RadiobuttonFieldRequest : FieldRequestBase
    {
        public override string type { get { return "radiobutton"; } }
        public Radio[] radio { get; set; }
    }
 
    public class SignatureFieldRequest : FieldRequestBase
    {
        public override string type { get { return "signature"; } }
    }
 
    public class AttachmentFieldRequest : LabelledFieldRequest
    {
        public override string type => "attachment";
    }
 
    public class Radio
    {
        public string radio_id { get; set; }
        public int page_number { get; set; }
        public int x { get; set; }
        public int y { get; set; }
        public double width { get; set; }
        public double height { get; set; }
        public int @checked { get; set; }
        public string value { get; set; }
        public int created { get; set; }
        public object[] json_attributes { get; set; }
    }
 
    public static class CalculatableValidatorId
    {
        public const string Number = "1109cfbbb06311a06a4c7f8d04f1f0d5c44103cb";
        public const string UsCurrency = "150662c7221a6a6ebcbb7c50ca46359d19757f81";
        public const string PositiveInteger = "1f9486ae822d30ba3df2cb8e65303ebfb8c803e8";
        public const string PositiveOrNegativeInteger = "23a57c29fa089e22bcf85d601c8091bc9c7da570";
        public const string UsInteger = "f031b8b63127c6915949bfc55e3cc81edbb12ecc";
        public const string UsPositiveInteger = "4cf9dfe7e65eb0a2c0c93e199f1ec1cdc23a267d";
        public const string EuInteger = "e8b7248b323525d1e8d5240ccf87d8c2926622cd";
        public const string EuPositiveInteger = "8937f6d0511167d67c6b21fe07c9ccd3a8116126";
    }
 
    public static class TextFieldValidatorId
    {
        public const string Email = "7cd795fd64ce63b670b52b2e83457d59ac796a39";
        public const string USPhone = "13cc1d661da456d27b249b73056ed4d1f2e72d8e";
        public const string State = "3123849de563f9e14acacc2739467e3d30e426b6";
        public const string Number = "1109cfbbb06311a06a4c7f8d04f1f0d5c44103cb";
        public const string UsCurrency = "150662c7221a6a6ebcbb7c50ca46359d19757f81";
        public const string Alphanumeric = "3859296fffd39cb8efeaffda5899973c014ce42e";
        public const string PositiveInteger = "1f9486ae822d30ba3df2cb8e65303ebfb8c803e8";
        public const string PositiveOrNegativeInteger = "23a57c29fa089e22bcf85d601c8091bc9c7da570";
        public const string Age = "1a203fa91791b0458608be045a454ba90557fb26";
        public const string SSN = "2cd795fd64ce63b670b52b2e83457d59ac796a39";
        public const string CreditCardNumber = "2f1c408bdf2f99fc5d4c342249da88ce5d2a5f02";
        public const string BankRTN = "959b068ef8ee5cc27e09ba79af58f9e805b7c2b3";
        public const string UsInteger = "f031b8b63127c6915949bfc55e3cc81edbb12ecc";
        public const string UsPositiveInteger = "4cf9dfe7e65eb0a2c0c93e199f1ec1cdc23a267d";
        public const string EuInteger = "e8b7248b323525d1e8d5240ccf87d8c2926622cd";
        public const string EuPositiveInteger = "8937f6d0511167d67c6b21fe07c9ccd3a8116126";
    }
 
    public static class DateFieldValidatorId
    {
        public const string DateUS = "13435fa6c2a17f83177fcbb5c4a9376ce85befeb";
        public const string DateEU = "059b068ef8ee5cc27e09ba79af58f9e805b7c2b3";
        public const string TimeOnly = "09d3bb6a5eb6598edb7bfad02b0143d8c68ad788";
        public const string WrittenDate = "0f4827a308018f98b11ae3923104685ff0c03070";
        public const string DateTime = "06448a0d0eb6a71c7c116ec4754bcb04ebf11da5";
    }
     
public partial class RestSharpSamples
    {
        public static void AddFillableFields(string accessToken, string apiUrl, string documentId, DocumentUpdateRequestModel documentUpdateRequest)
        {
            var client = new RestClient { BaseUrl = new Uri(apiUrl) };
            var request = new RestRequest($"/document/{documentId}", Method.PUT)
                .AddHeader("Accept", "application/json")
                .AddHeader("Authorization", $"Bearer {accessToken}");
            request.RequestFormat = DataFormat.Json;
            var requestJson = JsonConvert.SerializeObject(documentUpdateRequest);
            request.AddBody(requestJson);
            var response = client.Execute(request);
 
            if (response.StatusCode != HttpStatusCode.OK)
            {
                throw new Exception(response.Content);
            }
        }
    }  
 
 class Program
    {
        static void Main(string[] args)
        {
            var attachmentField = new AttachmentFieldRequest
            {
                height = 10,
                width = 50,
                label = "AttachMe",
                name = "AttachmentName",
                page_number = 0,
                required = true,
                role = "Signer 1",
                x = 20,
                y = 20
            };
            var checkboxField = new CheckboxFieldRequestModel
            {
                height = 10,
                width = 50,
                label = "Checkbox field",
                name = "Checkbox_field",
                page_number = 0,
                required = true,
                role = "Signer 1",
                x = 20,
                y = 40,
                prefilled_text = true
            };
            var datetimeField = new TextFieldRequest
            {
                height = 10,
                width = 80,
                label = "Datetime field",
                name = "Datetime_field",
                page_number = 0,
                prefilled_text = DateTime.Now.ToLongDateString(),
                required = true,
                role = "Signer 1",
                x = 100,
                y = 40,
                validator_id = DateFieldValidatorId.DateTime
            };
            var dropdownField = new DropdownFieldRequest
            {
                height = 10,
                width = 80,
                label = "Dropdown field",
                name = "Dropdown_field",
                page_number = 0,
                required = true,
                role = "Signer 1",
                x = 20,
                y = 60,
                custom_defined_option = true,
                enumeration_options = new[] { "10", "20", "30" }
            };
            var inititalsField = new InitialsFieldRequest
            {
                height = 40,
                width = 50,
                name = "Init",
                page_number = 0,
                required = true,
                role = "Signer 1",
                label = "Init label",
                x = 20,
                y = 80
            };
            var signatureField = new SignatureFieldRequest
            {
                height = 40,
                width = 50,
                name = "Sign",
                page_number = 0,
                required = true,
                role = "Signer 1",
                x = 120,
                y = 80
            };
            var textField = new TextFieldRequest
            {
                height = 10,
                width = 80,
                label = "Text field",
                name = "Text_field",
                page_number = 0,
                prefilled_text = "Prefilled text",
                required = true,
                role = "Signer 1",
                x = 20,
                y = 150
            };
            var calcField_number1 = new TextFieldRequest
            {
                height = 10,
                width = 50,
                label = "Number 1",
                name = "Number_1",
                page_number = 0,
                prefilled_text = "1",
                required = true,
                role = "Signer 1",
                x = 200,
                y = 20,
                validator_id = CalculatableValidatorId.Number
            };
            var calcField_number2 = new TextFieldRequest
            {
                height = 10,
                width = 50,
                label = "Number 2",
                name = "Number_2",
                page_number = 0,
                prefilled_text = "2",
                required = true,
                role = "Signer 1",
                x = 200,
                y = 40,
                validator_id = CalculatableValidatorId.PositiveInteger
            };
            var calcField_number3 = new TextFieldRequest
            {
                height = 10,
                width = 50,
                label = "Number 3",
                name = "Number_3",
                page_number = 0,
                prefilled_text = "3",
                required = true,
                role = "Signer 1",
                x = 200,
                y = 60,
                validator_id = CalculatableValidatorId.PositiveOrNegativeInteger
            };
            var calcField_number4 = new TextFieldRequest
            {
                height = 10,
                width = 50,
                label = "Number 4",
                name = "Number_4",
                page_number = 0,
                prefilled_text = "4",
                required = true,
                role = "Signer 1",
                x = 200,
                y = 80,
                validator_id = CalculatableValidatorId.EuInteger
            };
 
            var calculatedField = new CalculatedFieldRequest
            {
                height = 10,
                width = 50,
                label = "Calculated field",
                name = "Calculated_field",
                page_number = 0,
                required = true,
                role = "Signer 1",
                x = 300,
                y = 20,
                calculation_precision = 2
            };
            calculatedField.formula = $"({{{calcField_number1.name}}}+{{{calcField_number2.name}}})/{{{calcField_number3.name}}}-{{{calcField_number4.name}}}";
            calculatedField.calculation_formula = Formula.Div(Formula.Add(calcField_number1.name, calcField_number2.name), Formula.Sub(calcField_number3.name, calcField_number4.name));
 
            var documentUpdateRequest = new DocumentUpdateRequestModel();
            documentUpdateRequest.fields.Add(attachmentField);
            documentUpdateRequest.fields.Add(checkboxField);
            documentUpdateRequest.fields.Add(datetimeField);
            documentUpdateRequest.fields.Add(dropdownField);
            documentUpdateRequest.fields.Add(inititalsField);
            documentUpdateRequest.fields.Add(signatureField);
            documentUpdateRequest.fields.Add(textField);
            documentUpdateRequest.fields.Add(calcField_number1);
            documentUpdateRequest.fields.Add(calcField_number2);
            documentUpdateRequest.fields.Add(calcField_number3);
            documentUpdateRequest.fields.Add(calcField_number4);
            documentUpdateRequest.fields.Add(calculatedField);
 
            RestSharpSamples.AddFillableFields(Token.access_token, ApiBaseUrl, id, documentUpdateRequest);
        }
 
    }

import signnow_python_sdk
from datetime import datetime

if __name__ == '__main__':
    signnow_python_sdk.Config(client_id="CLIENT_ID",
                              client_secret="CLIENT_SECRET",
                              environment="production")

# Enter your own credentials
    username = "USER_NAME"
    password = "USER_PASSWORD"
    template_id = "TEMPLATE_ID"

# Create access_token for the user
    access_token = signnow_python_sdk.OAuth2.request_token(username, password, '*')

# Create the PUT /document payload
    doc_payload = {
        "texts": [
            {
                "size": 22,
                "x": 61,
                "y": 72,
                "page_number": 0,
                "font": "Arial",
                "data": "a sample text element",
                "line_height": 9.075,
                "client_timestamp": datetime.now().strftime("%s")
            }
        ],
        "fields": [
            {
                "x": 61,
                "y": 100,
                "width": 120,
                "height": 34,
                "page_number": 0,
                "role": "Signer 1",
                "required": True,
                "type": "signature"
            },
            {
                "x": 61,
                "y": 160,
                "width": 120,
                "height": 12,
                "page_number": 0,
                "label": "New Label",
                "role": "Signer 1",
                "required": True,
                "type": "text"
            },
            {
                "x": 61,
                "y": 178,
                "width": 41,
                "height": 26,
                "page_number": 0,
                "role": "Signer 2",
                "required": True,
                "type": "initials"
            }
        ]
    }

# Update document template with payload
    put_doc_response = signnow_python_sdk.Template.update(access_token['access_token'], template_id, doc_payload)

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Get started with uninterrupted eSignature API: send a document for signing and request attachments with C# SDK using the API

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 send a document for signing and request attachments with C# SDK using the API.

Send a document for signing and request attachments with C# SDK using the API 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 sales people engaged). Gain the ability to send a document for signing and request attachments with C# SDK using the API easily. Select signNow for more streamlined eSignature workflows.

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Use code samples to send a document for signing and request attachments with C# SDK using the API

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This service is really great! It has helped us enormously by ensuring we are fully covered in our agreements. We are on a 100% for collecting on our jobs, from a previous 60-70%. I recommend this to everyone.

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I've been using SignNow for years (since it was CudaSign). I started using 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 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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