Content Attributes

4/22/26About 2 min

Content Attributes

Content attributes are used to define the format and serialization method of the HTTP request body.

Request Body Attributes

JsonContentAttribute

Serialize parameter value as JSON content of the request:

public interface IUserApi
{
    [HttpPost("api/users")]
    Task<User> PostAsync([JsonContent] User user);
}

Supported properties:

CharSet: Encoding name, default is utf-8
AllowChunked: Whether to allow chunked transfer, default is true

XmlContentAttribute

Serialize parameter value as XML content of the request:

public interface IUserApi
{
    [HttpPost("api/users")]
    Task<User> PostAsync([XmlContent] User user);
}

Supported properties:

CharSet: Encoding name, default is utf-8

Form Attributes

FormContentAttribute

Use parameter value key-value pairs as x-www-form-urlencoded form:

public interface IUserApi
{
    [HttpPost("api/users")]
    Task<User> PostAsync([FormContent] User user);
}

Supported properties:

CollectionFormat: Collection format style, default is Multi

FormFieldAttribute

Constant value for x-www-form-urlencoded form field:

public interface IUserApi
{
    [FormField("fieldName1", "fieldValue1")]
    [FormField("fieldName2", "fieldValue2")]
    [HttpPost("api/users")]
    Task<User> PostAsync([FormContent] User user);
}

Use parameter value as x-www-form-urlencoded form field:

public interface IUserApi
{
    [HttpPost("api/users")]
    Task<User> PostAsync([FormContent] User user, [FormField] string field1);
}

FormDataContentAttribute

Use parameter value key-value pairs as multipart/form-data form:

public interface IUserApi
{
    [HttpPost("api/users")]
    Task<User> PostAsync([FormDataContent] User user, FormDataFile headImage);
}

Supported properties:

CollectionFormat: Collection format style, default is Multi

FormDataTextAttribute

Constant value for multipart/form-data form field:

public interface IUserApi
{
    [FormDataText("fieldName1", "fieldValue1")]
    [FormDataText("fieldName2", "fieldValue2")]
    [HttpPost("api/users")]
    Task<User> PostAsync([FormDataContent] User user);
}

Use parameter value as multipart/form-data form field:

public interface IUserApi
{
    [HttpPost("api/users")]
    Task<User> PostAsync([FormDataContent] User user, FormDataFile headImage, [FormDataText] string field1);
}

JsonFormFieldAttribute

Serialize parameter value as JSON string for form field:

public interface IUserApi
{
    [HttpPost("api/submit")]
    Task PostAsync([FormField] string field1, [JsonFormField] ComplexData field2);
}

JsonFormDataTextAttribute

Serialize parameter value as JSON string for multipart/form-data form field:

public interface IUserApi
{
    [HttpPost("api/submit")]
    Task PostAsync([FormDataContent] User user, [JsonFormDataText] ComplexData metadata);
}

Raw Content Attributes

RawStringContentAttribute

Raw text content:

public interface IUserApi
{
    [HttpPost]
    Task PostAsync([RawStringContent("text/plain")] string text);
}

Supported properties:

CharSet: Encoding name, default is utf-8

RawJsonContentAttribute

Raw json content:

public interface IUserApi
{
    [HttpPost]
    Task PostAsync([RawJsonContent] string json);
}

RawXmlContentAttribute

Raw xml content:

public interface IUserApi
{
    [HttpPost]
    Task PostAsync([RawXmlContent] string xml);
}

RawFormContentAttribute

Raw x-www-form-urlencoded form content. This content needs to be form-encoded:

public interface IUserApi
{
    [HttpPost]
    Task PostAsync([RawFormContent] string form);
}

Content Type Reference Table

Attribute	Content-Type
`[JsonContent]`	application/json
`[XmlContent]`	application/xml
`[FormContent]`	application/x-www-form-urlencoded
`[FormDataContent]`	multipart/form-data
`[JsonFormField]`	As form field, value is JSON string
`[JsonFormDataText]`	As multipart field, value is JSON string
`[RawStringContent]`	Custom
`[RawJsonContent]`	application/json
`[RawXmlContent]`	application/xml
`[RawFormContent]`	application/x-www-form-urlencoded