{
  "id": "api/common/http/HttpHeaders",
  "title": "HttpHeaders",
  "contents": "\n\n<article>\n  <div class=\"breadcrumb-container\">\n    <div class=\"breadcrumb\">\n      <script type=\"application/ld+json\">\n        {\n          \"@context\": \"http://schema.org\",\n          \"@type\": \"BreadcrumbList\",\n          \"itemListElement\": [\n            { \"@type\": \"ListItem\", \"position\": 1, \"item\": { \"@id\": \"https://angular.io//api\", \"name\": \"API\" } },\n            { \"@type\": \"ListItem\", \"position\": 2, \"item\": { \"@id\": \"https://angular.io/api/common\", \"name\": \"@angular/common\" } },\n            { \"@type\": \"ListItem\", \"position\": 3, \"item\": { \"@id\": \"https://angular.io/api/common/http\", \"name\": \"@angular/common/http\" } },\n            { \"@type\": \"ListItem\", \"position\": 4, \"item\": { \"@id\": \"https://angular.io/api/common/http/HttpHeaders\", \"name\": \"HttpHeaders\" } }\n          ]\n        }\n      </script>\n        <a href=\"/api\">API</a> > <a href=\"api/common\">@angular/common</a> > <a href=\"api/common/http\">@angular/common/http</a>\n    </div>\n    <div class=\"github-links\">\n  <a href=\"https://github.com/angular/angular/edit/master/packages/common/http/src/headers.ts?message=docs(common)%3A%20describe%20your%20change...#L14-L260\" aria-label=\"Suggest Edits\" title=\"Suggest Edits\"><i class=\"material-icons\" aria-hidden=\"true\" role=\"img\">mode_edit</i></a>\n  <a href=\"https://github.com/angular/angular/tree/12.0.0-next.7/packages/common/http/src/headers.ts#L14-L260\" aria-label=\"View Source\" title=\"View Source\"><i class=\"material-icons\" aria-hidden=\"true\" role=\"img\">code</i></a>\n</div>\n  </div>\n  \n  <header class=\"api-header\">\n    <h1 id=\"httpheaders\">HttpHeaders<a title=\"Link to this heading\" class=\"header-link\" aria-hidden=\"true\" href=\"api/common/http/HttpHeaders#httpheaders\"><i class=\"material-icons\">link</i></a></h1>\n    \n    <label class=\"api-type-label class\">class</label>\n    \n    \n    \n  </header>\n  \n  <aio-toc class=\"embedded\"></aio-toc>\n\n  <div class=\"api-body\">\n    \n  <section class=\"short-description\">\n    <p>Represents the header configuration options for an HTTP request.\nInstances are immutable. Modifying methods return a cloned\ninstance with the change. The original object is never changed.</p>\n\n    \n  </section>\n  \n  \n  \n  <section class=\"class-overview\">\n<code-example language=\"ts\" hidecopy=\"true\">\nclass <a href=\"api/common/http/HttpHeaders\" class=\"code-anchor\">HttpHeaders</a> {\n  <a class=\"code-anchor\" href=\"api/common/http/HttpHeaders#constructor()\"><span class=\"member-name\">constructor</span>(headers?: string | { [name: string]: string | string[]; })</a>\n  <a class=\"code-anchor\" href=\"api/common/http/HttpHeaders#has\"><span class=\"member-name\">has</span>(name: string): boolean</a>\n  <a class=\"code-anchor\" href=\"api/common/http/HttpHeaders#get\"><span class=\"member-name\">get</span>(name: string): string | null</a>\n  <a class=\"code-anchor\" href=\"api/common/http/HttpHeaders#keys\"><span class=\"member-name\">keys</span>(): string[]</a>\n  <a class=\"code-anchor\" href=\"api/common/http/HttpHeaders#getAll\"><span class=\"member-name\">getAll</span>(name: string): string[] | null</a>\n  <a class=\"code-anchor\" href=\"api/common/http/HttpHeaders#append\"><span class=\"member-name\">append</span>(name: string, value: string | string[]): HttpHeaders</a>\n  <a class=\"code-anchor\" href=\"api/common/http/HttpHeaders#set\"><span class=\"member-name\">set</span>(name: string, value: string | string[]): HttpHeaders</a>\n  <a class=\"code-anchor\" href=\"api/common/http/HttpHeaders#delete\"><span class=\"member-name\">delete</span>(name: string, value?: string | string[]): HttpHeaders</a>\n}\n</code-example>\n\n  \n  \n\n</section>\n\n\n  \n\n  \n  \n  \n\n\n\n\n\n\n<h2 id=\"constructor\">Constructor<a title=\"Link to this heading\" class=\"header-link\" aria-hidden=\"true\" href=\"api/common/http/HttpHeaders#constructor\"><i class=\"material-icons\">link</i></a></h2>\n<a id=\"constructor()\"></a>\n<table class=\"is-full-width method-table constructor\">\n  \n  <tbody>\n    <tr>\n      <td class=\"short-description\">\n        <p>Constructs a new HTTP header object with the given values.</p>\n\n      </td>\n    </tr>\n  \n    <tr>\n      <td>\n        <div class=\"overload-info\">\n  \n\n  <code-example language=\"ts\" hidecopy=\"true\" class=\"no-box api-heading\"><span class=\"member-name\">constructor</span>(headers?: string | { [name: string]: string | string[]; })</code-example>\n\n  \n\n  <h6 class=\"no-anchor\" id=\"parameters\">Parameters</h6>\n  <table class=\"is-full-width list-table parameters-table constructor-overload-parameters\">\n  <tbody>\n  \n    <tr class=\"constructor-overload-parameter\">\n      <td class=\"param-name\">\n        <a id=\"\"></a>\n        <code>headers</code>\n      </td>\n      <td class=\"param-type\"><code>string | { [name: string]: string | string[]; }</code></td>\n      <td class=\"param-description\">\n            <p>Optional. Default is <code>undefined</code>.</p>\n      \n      </td>\n    </tr>\n  </tbody>\n</table>\n\n  \n\n\n  \n\n  \n</div>\n      </td>\n    </tr>\n  \n\n  \n\n  \n    </tbody>\n</table>\n\n\n\n\n\n\n\n\n<section class=\"instance-methods\">\n  <h2 id=\"methods\">Methods<a title=\"Link to this heading\" class=\"header-link\" aria-hidden=\"true\" href=\"api/common/http/HttpHeaders#methods\"><i class=\"material-icons\">link</i></a></h2>\n  \n    <a id=\"has\"></a>\n<table class=\"is-full-width method-table instance-method\">\n  <thead><tr><th>\n    <div class=\"with-github-links\">\n    <h3 id=\"has\">\n      has()\n      \n    <a title=\"Link to this heading\" class=\"header-link\" aria-hidden=\"true\" href=\"api/common/http/HttpHeaders#has\"><i class=\"material-icons\">link</i></a></h3>\n    <div class=\"github-links\">\n  <a href=\"https://github.com/angular/angular/edit/master/packages/common/http/src/headers.ts?message=docs(common)%3A%20describe%20your%20change...#L86-L98\" aria-label=\"Suggest Edits\" title=\"Suggest Edits\"><i class=\"material-icons\" aria-hidden=\"true\" role=\"img\">mode_edit</i></a>\n  <a href=\"https://github.com/angular/angular/tree/12.0.0-next.7/packages/common/http/src/headers.ts#L86-L98\" aria-label=\"View Source\" title=\"View Source\"><i class=\"material-icons\" aria-hidden=\"true\" role=\"img\">code</i></a>\n</div>\n    </div>\n  </th></tr></thead>\n  <tbody>\n    <tr>\n      <td class=\"short-description\">\n        <p>Checks for existence of a given header.</p>\n\n      </td>\n    </tr>\n  \n    <tr>\n      <td>\n        <div class=\"overload-info\">\n  \n\n  <code-example language=\"ts\" hidecopy=\"true\" class=\"no-box api-heading\"><span class=\"member-name\">has</span>(name: string): boolean</code-example>\n\n  \n\n  <h6 class=\"no-anchor\" id=\"parameters-1\">Parameters</h6>\n  <table class=\"is-full-width list-table parameters-table instance-method-overload-parameters\">\n  <tbody>\n  \n    <tr class=\"instance-method-overload-parameter\">\n      <td class=\"param-name\">\n        <a id=\"\"></a>\n        <code>name</code>\n      </td>\n      <td class=\"param-type\"><code>string</code></td>\n      <td class=\"param-description\">\n      <p>The header name to check for existence.</p>\n\n      </td>\n    </tr>\n  </tbody>\n</table>\n\n  \n  <h6 class=\"no-anchor\" id=\"returns\">Returns</h6>\n  <p><code>boolean</code>: True if the header exists, false otherwise.</p>\n\n  \n\n\n  \n\n  \n</div>\n      </td>\n    </tr>\n  \n\n  \n\n  \n    </tbody>\n</table>\n\n  \n    <a id=\"get\"></a>\n<table class=\"is-full-width method-table instance-method\">\n  <thead><tr><th>\n    <div class=\"with-github-links\">\n    <h3 id=\"get\">\n      get()\n      \n    <a title=\"Link to this heading\" class=\"header-link\" aria-hidden=\"true\" href=\"api/common/http/HttpHeaders#get\"><i class=\"material-icons\">link</i></a></h3>\n    <div class=\"github-links\">\n  <a href=\"https://github.com/angular/angular/edit/master/packages/common/http/src/headers.ts?message=docs(common)%3A%20describe%20your%20change...#L99-L112\" aria-label=\"Suggest Edits\" title=\"Suggest Edits\"><i class=\"material-icons\" aria-hidden=\"true\" role=\"img\">mode_edit</i></a>\n  <a href=\"https://github.com/angular/angular/tree/12.0.0-next.7/packages/common/http/src/headers.ts#L99-L112\" aria-label=\"View Source\" title=\"View Source\"><i class=\"material-icons\" aria-hidden=\"true\" role=\"img\">code</i></a>\n</div>\n    </div>\n  </th></tr></thead>\n  <tbody>\n    <tr>\n      <td class=\"short-description\">\n        <p>Retrieves the first value of a given header.</p>\n\n      </td>\n    </tr>\n  \n    <tr>\n      <td>\n        <div class=\"overload-info\">\n  \n\n  <code-example language=\"ts\" hidecopy=\"true\" class=\"no-box api-heading\"><span class=\"member-name\">get</span>(name: string): string | null</code-example>\n\n  \n\n  <h6 class=\"no-anchor\" id=\"parameters-2\">Parameters</h6>\n  <table class=\"is-full-width list-table parameters-table instance-method-overload-parameters\">\n  <tbody>\n  \n    <tr class=\"instance-method-overload-parameter\">\n      <td class=\"param-name\">\n        <a id=\"\"></a>\n        <code>name</code>\n      </td>\n      <td class=\"param-type\"><code>string</code></td>\n      <td class=\"param-description\">\n      <p>The header name.</p>\n\n      </td>\n    </tr>\n  </tbody>\n</table>\n\n  \n  <h6 class=\"no-anchor\" id=\"returns-1\">Returns</h6>\n  <p><code>string | null</code>: The value string if the header exists, null otherwise</p>\n\n  \n\n\n  \n\n  \n</div>\n      </td>\n    </tr>\n  \n\n  \n\n  \n    </tbody>\n</table>\n\n  \n    <a id=\"keys\"></a>\n<table class=\"is-full-width method-table instance-method\">\n  <thead><tr><th>\n    <div class=\"with-github-links\">\n    <h3 id=\"keys\">\n      keys()\n      \n    <a title=\"Link to this heading\" class=\"header-link\" aria-hidden=\"true\" href=\"api/common/http/HttpHeaders#keys\"><i class=\"material-icons\">link</i></a></h3>\n    <div class=\"github-links\">\n  <a href=\"https://github.com/angular/angular/edit/master/packages/common/http/src/headers.ts?message=docs(common)%3A%20describe%20your%20change...#L113-L123\" aria-label=\"Suggest Edits\" title=\"Suggest Edits\"><i class=\"material-icons\" aria-hidden=\"true\" role=\"img\">mode_edit</i></a>\n  <a href=\"https://github.com/angular/angular/tree/12.0.0-next.7/packages/common/http/src/headers.ts#L113-L123\" aria-label=\"View Source\" title=\"View Source\"><i class=\"material-icons\" aria-hidden=\"true\" role=\"img\">code</i></a>\n</div>\n    </div>\n  </th></tr></thead>\n  <tbody>\n    <tr>\n      <td class=\"short-description\">\n        <p>Retrieves the names of the headers.</p>\n\n      </td>\n    </tr>\n  \n    <tr>\n      <td>\n        <div class=\"overload-info\">\n  \n\n  <code-example language=\"ts\" hidecopy=\"true\" class=\"no-box api-heading\"><span class=\"member-name\">keys</span>(): string[]</code-example>\n\n  \n\n  <h6 class=\"no-anchor\" id=\"parameters-3\">Parameters</h6>\n  <p>There are no parameters.</p>\n\n  \n  <h6 class=\"no-anchor\" id=\"returns-2\">Returns</h6>\n  <p><code>string[]</code>: A list of header names.</p>\n\n  \n\n\n  \n\n  \n</div>\n      </td>\n    </tr>\n  \n\n  \n\n  \n    </tbody>\n</table>\n\n  \n    <a id=\"getAll\"></a>\n<table class=\"is-full-width method-table instance-method\">\n  <thead><tr><th>\n    <div class=\"with-github-links\">\n    <h3 id=\"getall\">\n      getAll()\n      \n    <a title=\"Link to this heading\" class=\"header-link\" aria-hidden=\"true\" href=\"api/common/http/HttpHeaders#getall\"><i class=\"material-icons\">link</i></a></h3>\n    <div class=\"github-links\">\n  <a href=\"https://github.com/angular/angular/edit/master/packages/common/http/src/headers.ts?message=docs(common)%3A%20describe%20your%20change...#L124-L136\" aria-label=\"Suggest Edits\" title=\"Suggest Edits\"><i class=\"material-icons\" aria-hidden=\"true\" role=\"img\">mode_edit</i></a>\n  <a href=\"https://github.com/angular/angular/tree/12.0.0-next.7/packages/common/http/src/headers.ts#L124-L136\" aria-label=\"View Source\" title=\"View Source\"><i class=\"material-icons\" aria-hidden=\"true\" role=\"img\">code</i></a>\n</div>\n    </div>\n  </th></tr></thead>\n  <tbody>\n    <tr>\n      <td class=\"short-description\">\n        <p>Retrieves a list of values for a given header.</p>\n\n      </td>\n    </tr>\n  \n    <tr>\n      <td>\n        <div class=\"overload-info\">\n  \n\n  <code-example language=\"ts\" hidecopy=\"true\" class=\"no-box api-heading\"><span class=\"member-name\">getAll</span>(name: string): string[] | null</code-example>\n\n  \n\n  <h6 class=\"no-anchor\" id=\"parameters-4\">Parameters</h6>\n  <table class=\"is-full-width list-table parameters-table instance-method-overload-parameters\">\n  <tbody>\n  \n    <tr class=\"instance-method-overload-parameter\">\n      <td class=\"param-name\">\n        <a id=\"\"></a>\n        <code>name</code>\n      </td>\n      <td class=\"param-type\"><code>string</code></td>\n      <td class=\"param-description\">\n      <p>The header name from which to retrieve values.</p>\n\n      </td>\n    </tr>\n  </tbody>\n</table>\n\n  \n  <h6 class=\"no-anchor\" id=\"returns-3\">Returns</h6>\n  <p><code>string[] | null</code>: A string of values if the header exists, null otherwise.</p>\n\n  \n\n\n  \n\n  \n</div>\n      </td>\n    </tr>\n  \n\n  \n\n  \n    </tbody>\n</table>\n\n  \n    <a id=\"append\"></a>\n<table class=\"is-full-width method-table instance-method\">\n  <thead><tr><th>\n    <div class=\"with-github-links\">\n    <h3 id=\"append\">\n      append()\n      \n    <a title=\"Link to this heading\" class=\"header-link\" aria-hidden=\"true\" href=\"api/common/http/HttpHeaders#append\"><i class=\"material-icons\">link</i></a></h3>\n    <div class=\"github-links\">\n  <a href=\"https://github.com/angular/angular/edit/master/packages/common/http/src/headers.ts?message=docs(common)%3A%20describe%20your%20change...#L137-L150\" aria-label=\"Suggest Edits\" title=\"Suggest Edits\"><i class=\"material-icons\" aria-hidden=\"true\" role=\"img\">mode_edit</i></a>\n  <a href=\"https://github.com/angular/angular/tree/12.0.0-next.7/packages/common/http/src/headers.ts#L137-L150\" aria-label=\"View Source\" title=\"View Source\"><i class=\"material-icons\" aria-hidden=\"true\" role=\"img\">code</i></a>\n</div>\n    </div>\n  </th></tr></thead>\n  <tbody>\n    <tr>\n      <td class=\"short-description\">\n        <p>Appends a new value to the existing set of values for a header\nand returns them in a clone of the original instance.</p>\n\n      </td>\n    </tr>\n  \n    <tr>\n      <td>\n        <div class=\"overload-info\">\n  \n\n  <code-example language=\"ts\" hidecopy=\"true\" class=\"no-box api-heading\"><span class=\"member-name\">append</span>(name: string, value: string | string[]): <a href=\"api/common/http/HttpHeaders\" class=\"code-anchor\">HttpHeaders</a></code-example>\n\n  \n\n  <h6 class=\"no-anchor\" id=\"parameters-5\">Parameters</h6>\n  <table class=\"is-full-width list-table parameters-table instance-method-overload-parameters\">\n  <tbody>\n  \n    <tr class=\"instance-method-overload-parameter\">\n      <td class=\"param-name\">\n        <a id=\"\"></a>\n        <code>name</code>\n      </td>\n      <td class=\"param-type\"><code>string</code></td>\n      <td class=\"param-description\">\n      <p>The header name for which to append the values.</p>\n\n      </td>\n    </tr>\n    <tr class=\"instance-method-overload-parameter\">\n      <td class=\"param-name\">\n        <a id=\"\"></a>\n        <code>value</code>\n      </td>\n      <td class=\"param-type\"><code>string | string[]</code></td>\n      <td class=\"param-description\">\n      <p>The value to append.</p>\n\n      </td>\n    </tr>\n  </tbody>\n</table>\n\n  \n  <h6 class=\"no-anchor\" id=\"returns-4\">Returns</h6>\n  <p><code><a href=\"api/common/http/HttpHeaders\" class=\"code-anchor\">HttpHeaders</a></code>: A clone of the HTTP headers object with the value appended to the given header.</p>\n\n  \n\n\n  \n\n  \n</div>\n      </td>\n    </tr>\n  \n\n  \n\n  \n    </tbody>\n</table>\n\n  \n    <a id=\"set\"></a>\n<table class=\"is-full-width method-table instance-method\">\n  <thead><tr><th>\n    <div class=\"with-github-links\">\n    <h3 id=\"set\">\n      set()\n      \n    <a title=\"Link to this heading\" class=\"header-link\" aria-hidden=\"true\" href=\"api/common/http/HttpHeaders#set\"><i class=\"material-icons\">link</i></a></h3>\n    <div class=\"github-links\">\n  <a href=\"https://github.com/angular/angular/edit/master/packages/common/http/src/headers.ts?message=docs(common)%3A%20describe%20your%20change...#L151-L163\" aria-label=\"Suggest Edits\" title=\"Suggest Edits\"><i class=\"material-icons\" aria-hidden=\"true\" role=\"img\">mode_edit</i></a>\n  <a href=\"https://github.com/angular/angular/tree/12.0.0-next.7/packages/common/http/src/headers.ts#L151-L163\" aria-label=\"View Source\" title=\"View Source\"><i class=\"material-icons\" aria-hidden=\"true\" role=\"img\">code</i></a>\n</div>\n    </div>\n  </th></tr></thead>\n  <tbody>\n    <tr>\n      <td class=\"short-description\">\n        <p>Sets or modifies a value for a given header in a clone of the original instance.\nIf the header already exists, its value is replaced with the given value\nin the returned object.</p>\n\n      </td>\n    </tr>\n  \n    <tr>\n      <td>\n        <div class=\"overload-info\">\n  \n\n  <code-example language=\"ts\" hidecopy=\"true\" class=\"no-box api-heading\"><span class=\"member-name\">set</span>(name: string, value: string | string[]): <a href=\"api/common/http/HttpHeaders\" class=\"code-anchor\">HttpHeaders</a></code-example>\n\n  \n\n  <h6 class=\"no-anchor\" id=\"parameters-6\">Parameters</h6>\n  <table class=\"is-full-width list-table parameters-table instance-method-overload-parameters\">\n  <tbody>\n  \n    <tr class=\"instance-method-overload-parameter\">\n      <td class=\"param-name\">\n        <a id=\"\"></a>\n        <code>name</code>\n      </td>\n      <td class=\"param-type\"><code>string</code></td>\n      <td class=\"param-description\">\n      <p>The header name.</p>\n\n      </td>\n    </tr>\n    <tr class=\"instance-method-overload-parameter\">\n      <td class=\"param-name\">\n        <a id=\"\"></a>\n        <code>value</code>\n      </td>\n      <td class=\"param-type\"><code>string | string[]</code></td>\n      <td class=\"param-description\">\n      <p>The value or values to set or overide for the given header.</p>\n\n      </td>\n    </tr>\n  </tbody>\n</table>\n\n  \n  <h6 class=\"no-anchor\" id=\"returns-5\">Returns</h6>\n  <p><code><a href=\"api/common/http/HttpHeaders\" class=\"code-anchor\">HttpHeaders</a></code>: A clone of the HTTP headers object with the newly set header value.</p>\n\n  \n\n\n  \n\n  \n</div>\n      </td>\n    </tr>\n  \n\n  \n\n  \n    </tbody>\n</table>\n\n  \n    <a id=\"delete\"></a>\n<table class=\"is-full-width method-table instance-method\">\n  <thead><tr><th>\n    <div class=\"with-github-links\">\n    <h3 id=\"delete\">\n      delete()\n      \n    <a title=\"Link to this heading\" class=\"header-link\" aria-hidden=\"true\" href=\"api/common/http/HttpHeaders#delete\"><i class=\"material-icons\">link</i></a></h3>\n    <div class=\"github-links\">\n  <a href=\"https://github.com/angular/angular/edit/master/packages/common/http/src/headers.ts?message=docs(common)%3A%20describe%20your%20change...#L164-L174\" aria-label=\"Suggest Edits\" title=\"Suggest Edits\"><i class=\"material-icons\" aria-hidden=\"true\" role=\"img\">mode_edit</i></a>\n  <a href=\"https://github.com/angular/angular/tree/12.0.0-next.7/packages/common/http/src/headers.ts#L164-L174\" aria-label=\"View Source\" title=\"View Source\"><i class=\"material-icons\" aria-hidden=\"true\" role=\"img\">code</i></a>\n</div>\n    </div>\n  </th></tr></thead>\n  <tbody>\n    <tr>\n      <td class=\"short-description\">\n        <p>Deletes values for a given header in a clone of the original instance.</p>\n\n      </td>\n    </tr>\n  \n    <tr>\n      <td>\n        <div class=\"overload-info\">\n  \n\n  <code-example language=\"ts\" hidecopy=\"true\" class=\"no-box api-heading\"><span class=\"member-name\">delete</span>(name: string, value?: string | string[]): <a href=\"api/common/http/HttpHeaders\" class=\"code-anchor\">HttpHeaders</a></code-example>\n\n  \n\n  <h6 class=\"no-anchor\" id=\"parameters-7\">Parameters</h6>\n  <table class=\"is-full-width list-table parameters-table instance-method-overload-parameters\">\n  <tbody>\n  \n    <tr class=\"instance-method-overload-parameter\">\n      <td class=\"param-name\">\n        <a id=\"\"></a>\n        <code>name</code>\n      </td>\n      <td class=\"param-type\"><code>string</code></td>\n      <td class=\"param-description\">\n      <p>The header name.</p>\n\n      </td>\n    </tr>\n    <tr class=\"instance-method-overload-parameter\">\n      <td class=\"param-name\">\n        <a id=\"\"></a>\n        <code>value</code>\n      </td>\n      <td class=\"param-type\"><code>string | string[]</code></td>\n      <td class=\"param-description\">\n      <p>The value or values to delete for the given header.</p>\n<p>      Optional. Default is <code>undefined</code>.</p>\n\n      </td>\n    </tr>\n  </tbody>\n</table>\n\n  \n  <h6 class=\"no-anchor\" id=\"returns-6\">Returns</h6>\n  <p><code><a href=\"api/common/http/HttpHeaders\" class=\"code-anchor\">HttpHeaders</a></code>: A clone of the HTTP headers object with the given value deleted.</p>\n\n  \n\n\n  \n\n  \n</div>\n      </td>\n    </tr>\n  \n\n  \n\n  \n    </tbody>\n</table>\n\n  \n</section>\n\n\n\n  \n\n\n  </div>\n</article>\n\n<!-- links to this doc:\n - api/common/http\n - api/common/http/HttpClient\n - api/common/http/HttpErrorResponse\n - api/common/http/HttpHeaderResponse\n - api/common/http/HttpRequest\n - api/common/http/HttpResponse\n - api/common/http/HttpResponseBase\n - api/common/http/testing/TestRequest\n - guide/http\n - tutorial/toh-pt6\n-->\n<!-- links from this doc:\n - /api\n - api/common\n - api/common/http\n - api/common/http/HttpHeaders#append\n - api/common/http/HttpHeaders#constructor\n - api/common/http/HttpHeaders#constructor()\n - api/common/http/HttpHeaders#delete\n - api/common/http/HttpHeaders#get\n - api/common/http/HttpHeaders#getAll\n - api/common/http/HttpHeaders#getall\n - api/common/http/HttpHeaders#has\n - api/common/http/HttpHeaders#httpheaders\n - api/common/http/HttpHeaders#keys\n - api/common/http/HttpHeaders#methods\n - api/common/http/HttpHeaders#set\n - https://github.com/angular/angular/edit/master/packages/common/http/src/headers.ts?message=docs(common)%3A%20describe%20your%20change...#L113-L123\n - https://github.com/angular/angular/edit/master/packages/common/http/src/headers.ts?message=docs(common)%3A%20describe%20your%20change...#L124-L136\n - https://github.com/angular/angular/edit/master/packages/common/http/src/headers.ts?message=docs(common)%3A%20describe%20your%20change...#L137-L150\n - https://github.com/angular/angular/edit/master/packages/common/http/src/headers.ts?message=docs(common)%3A%20describe%20your%20change...#L14-L260\n - https://github.com/angular/angular/edit/master/packages/common/http/src/headers.ts?message=docs(common)%3A%20describe%20your%20change...#L151-L163\n - https://github.com/angular/angular/edit/master/packages/common/http/src/headers.ts?message=docs(common)%3A%20describe%20your%20change...#L164-L174\n - https://github.com/angular/angular/edit/master/packages/common/http/src/headers.ts?message=docs(common)%3A%20describe%20your%20change...#L86-L98\n - https://github.com/angular/angular/edit/master/packages/common/http/src/headers.ts?message=docs(common)%3A%20describe%20your%20change...#L99-L112\n - https://github.com/angular/angular/tree/12.0.0-next.7/packages/common/http/src/headers.ts#L113-L123\n - https://github.com/angular/angular/tree/12.0.0-next.7/packages/common/http/src/headers.ts#L124-L136\n - https://github.com/angular/angular/tree/12.0.0-next.7/packages/common/http/src/headers.ts#L137-L150\n - https://github.com/angular/angular/tree/12.0.0-next.7/packages/common/http/src/headers.ts#L14-L260\n - https://github.com/angular/angular/tree/12.0.0-next.7/packages/common/http/src/headers.ts#L151-L163\n - https://github.com/angular/angular/tree/12.0.0-next.7/packages/common/http/src/headers.ts#L164-L174\n - https://github.com/angular/angular/tree/12.0.0-next.7/packages/common/http/src/headers.ts#L86-L98\n - https://github.com/angular/angular/tree/12.0.0-next.7/packages/common/http/src/headers.ts#L99-L112\n-->"
}