FormData

FormData.prototype.delete

Deletes a key and all its values from a FormData object

Syntax

JavaScript
formData.delete(name)

Parameters

ParameterTypeDescription
namestringThe name of the key to delete

Return Value

undefined

Examples

Basic Usage
const fd = new FormData()
fd.append('name', 'Alice')
fd.delete('name')
console.log(fd.has('name')) // false
Practical Example
function sanitizeFormData(fd: FormData, exclude: string[]) {
  exclude.forEach(key => fd.delete(key))
  return fd
}
Advanced Usage
const fd = new FormData()
fd.append('token', 'secret')
fd.append('data', 'value')
fd.delete('token')
console.log([...fd.keys()]) // ['data']

Understanding FormData.prototype.delete

The FormData.prototype.delete method in JavaScript deletes a key and all its values from a FormData object. It belongs to the FormData object and is one of the most widely used methods for working with formdata values in modern JavaScript and TypeScript applications.

The method signature is formData.delete(name). It accepts 1 parameter: name. When called, it returns undefined. Understanding when and how to use delete() helps you write more expressive, readable code.

Common use cases for FormData.prototype.delete include data transformation, input validation, API response processing, and building reusable utility functions. It works well alongside related methods like fetch-formdata-get, fetch-formdata-set, fetch-formdata-append, enabling you to chain operations together for complex data manipulation pipelines.

Browser support for FormData.prototype.delete is excellent across all modern browsers including Chrome, Firefox, Safari, and Edge. It is also fully supported in Node.js and Deno. For older environments, transpilation with Babel or a polyfill may be needed.

Browser Compatibility

Supported in all modern browsers (Chrome, Firefox, Safari, Edge) and Node.js. Part of the ECMAScript standard.

Related Methods

More FormData Methods

Other methods in the FormData object

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