網址編碼
透過集合功能整理內容
你可以依據偏好儲存及分類內容。
有些字元 (例如空格) 不能放進網址，另外有些字元在網址內則具有特殊意義。在 HTML 表單中，= 字元可用來區隔名稱和值。URI 一般語法會使用網址編碼來處理這個問題，HTML 表單則會進行額外的替代作業，而非對所有這類字元進行百分比編碼。
舉例來說，字串中的空格不是以 %20 編碼，就是以加號 (+) 取而代之。如果您使用縱線字元 (|) 做為分隔符，請務必將縱線編碼為 %7C。字串中的半形逗號應編碼為 %2C。
建議您使用平台的一般網址建構程式庫來自動編碼網址，確保平台網址能正確逸出。
建立有效網址
您可能認為網址是否「有效」一眼就能判斷，但實際情況不然。例如，在瀏覽器的網址列內輸入的網址可能包含特殊字元 (例如 "上海+中國")；瀏覽器必須在內部將這些字元轉譯為其他編碼方式才能傳送。同理可證，產生或接受 UTF-8 輸入值的任何程式碼都可能會將含有 UTF-8 字元的網址視為「有效網址」，但也需要先轉譯這些字元，才能向外傳送至網路伺服器。這個過程稱為網址編碼或百分比編碼。
特殊字元
所有網址都必須符合統一資源 ID (URI) 規格指定的語法，因此我們必須轉譯特殊字元。事實上，這表示網址必須僅包含一個特殊的 ASCII 字元子集：慣用的英數字元符號，以及用做網址內控制字元的部分預留字元。下表摘要列出這些字元：
有效網址字元摘要
| 字元集 | 字元 | 網址使用情況 |
| 英數字元 |
a b c d e f g h i j k l m
n o p q r s t u v w x y z
A B C D E F G H I J K L M
N O P Q R S T U V W X Y Z
0 1 2 3 4 5 6 7 8 9
| 文字字串、結構用途 (http)、通訊埠 (8080) 等。 |
| 非預留 |
- _ . ~ |
文字字串 |
| 預留 |
! * ' ( ) ; : @ & = + $ , / ? % # [ ] |
控制字元和/或文字字串 |
建立有效網址時，您必須確認網址僅包含「有效網址字元摘要」表格中列出的字元。如果網址使用上述字元集，通常會導致兩個問題：一個是遺漏問題，一個則是代換問題：
- 您希望處理的字元不屬於上述字元集。舉例來說，外國語言的字元 (例如「
上海+中國」) 就需要使用上述字元加以編碼。依照普遍慣例，空格 (網址內不允許使用) 通常也用加號 '+' 字元來表示。
- 在上述字元集中以預留字元形式列出的字元，但需依照字面意思使用。舉例來說，網址內會使用
? 來表示查詢字串的開頭；如果您想使用「? and the Mysterions」這個字串，就必須對 '?' 字元進行編碼。
遵守網址編碼原則的所有字元，都會使用 '%' 字元，以及對應至相關 UTF-8 字元的雙字元十六進位值進行編碼。舉例來說，採用 UTF-8 編碼的「上海+中國」改用網址編碼時，會成為 %E4%B8%8A%E6%B5%B7%2B%E4%B8%AD%E5%9C%8B。字串「? and the Mysterians」進行網址編碼後，會成為 %3F+and+the+Mysterians 或 %3F%20and%20the%20Mysterians。
需要編碼的常見字元
必須編碼的部分常見字元如下：
| 不安全的字元 |
經過編碼的值 |
| 空格 |
%20 |
| " |
%22 |
| < |
%3C |
| > |
%3E |
| # |
%23 |
| % |
%25 |
| | |
%7C |
轉換您從使用者輸入內容中取得的網址，有時並不容易處理。舉例來說，使用者輸入的地址可能是「5th&Main St.」。一般來說，您應該根據各組成部分來建立網址，並將任何使用者輸入內容當成常值字元來處理。
此外，所有 Google 地圖平台網路服務和 Static Web API 的網址長度上限都是 8,192 個字元。對於大部分的服務而言，很少出現接近此字元限制的情況。但請注意，某些服務的幾個參數可能會產生較長的網址。
除非另有註明，否則本頁面中的內容是採用創用 CC 姓名標示 4.0 授權，程式碼範例則為阿帕契 2.0 授權。詳情請參閱《Google Developers 網站政策》。Java 是 Oracle 和/或其關聯企業的註冊商標。
上次更新時間：2023-08-02 (世界標準時間)。
[null,null,["上次更新時間：2023-08-02 (世界標準時間)。"],[[["\u003cp\u003eURLs can only contain a specific set of ASCII characters and some reserved characters, requiring encoding of other characters.\u003c/p\u003e\n"],["\u003cp\u003eURL encoding involves replacing unsafe characters with a '%' followed by their two-digit hexadecimal UTF-8 representation.\u003c/p\u003e\n"],["\u003cp\u003eCharacters like spaces, quotation marks, less than, greater than, hash, percent, and pipe often require URL encoding.\u003c/p\u003e\n"],["\u003cp\u003eBuilding URLs programmatically using platform libraries is recommended for automatic and proper encoding.\u003c/p\u003e\n"],["\u003cp\u003eGoogle Maps Platform web services and static web APIs have a URL character limit of 16384.\u003c/p\u003e\n"]]],["URLs require encoding because they only accept a specific subset of ASCII characters. Special characters, like spaces and foreign language characters, must be encoded using percent encoding (e.g., `%20` for space) or plus signs in specific instances. Reserved characters, such as `=`, `?`, and `|`, also need encoding when used literally, not as control characters. It's best to utilize platform URL building libraries for automatic encoding, guaranteeing proper escaping, because it can be complex to do manually. It is also important to note that URLs are limited to 16384 characters for Google Maps Platform web services.\n"],null,["Some characters cannot be part of a URL (for example, the space) and some other\ncharacters have a special meaning in a URL. In HTML forms, the character `=` is\nused to separate a name from a value. The URI generic syntax uses URL encoding\nto deal with this problem, while HTML forms make some additional substitutions\nrather than applying percent encoding for all such characters.\n\nFor example, spaces in a string are either encoded with `%20` or replaced with\nthe plus sign (`+`). If you use a pipe character (`|`) as a separator, be sure\nto encode the pipe as `%7C`. A comma in a string should be encoded as `%2C`.\n\nIt is recommended you use your platform's normal URL building libraries to\nautomatically encode your URLs, to ensure the URLs are properly escaped for your\nplatform.\n\nBuilding a valid URL\n\nYou may think that a \"valid\" URL is self-evident, but\nthat's not quite the case. A URL entered within an address bar in a\nbrowser, for example, may contain special characters (e.g.\n`\"上海+中國\"`); the browser needs to internally translate\nthose characters into a different encoding before transmission.\nBy the same token, any code that generates or accepts UTF-8 input\nmight treat URLs with UTF-8 characters as \"valid\", but would also need\nto translate those characters before sending them out to a web server.\nThis process is called [URL-encoding](https://en.wikipedia.org/wiki/Query_string#URL_encoding) or [percent-encoding](https://en.wikipedia.org/wiki/Percent-encoding).\n\nSpecial characters\n\nWe need to translate special characters because\nall URLs need to conform to the syntax specified by the\n[Uniform\nResource Identifier (URI)](http://tools.ietf.org/html/rfc3986) specification. In effect, this means that URLs\nmust contain only a special subset of ASCII characters: the familiar\nalphanumeric symbols, and some reserved characters for use as control\ncharacters within URLs. This table summarizes these characters:\nSummary of Valid URL Characters\n\n| Set | characters | URL usage |\n|--------------|-----------------------------------------------------------------------------------------------------------------------------|----------------------------------------------------------|\n| Alphanumeric | a b c d e f g h i j k l m n o p q r s t u v w x y z A B C D E F G H I J K L M N O P Q R S T U V W X Y Z 0 1 2 3 4 5 6 7 8 9 | Text strings, scheme usage (`http`), port (`8080`), etc. |\n| Unreserved | - _ . \\~ | Text strings |\n| Reserved | ! \\* ' ( ) ; : @ \\& = + $ , / ? % # \\[ \\] | Control characters and/or Text Strings |\n\nWhen building a valid URL, you must ensure that it contains only those characters shown in the\ntable. Conforming a URL to use this set of characters generally\nleads to two issues, one of omission and one of substitution:\n\n- Characters that you wish to handle exist outside of the above set. For example, characters in foreign languages such as `上海+中國` need to be encoded using the above characters. By popular convention, spaces (which are not allowed within URLs) are often represented using the plus `'+'` character as well.\n- Characters exist within the above set as reserved characters, but need to be used literally. For example, `?` is used within URLs to indicate the beginning of the query string; if you wish to use the string \"? and the Mysterions,\" you'd need to encode the `'?'` character.\n\nAll characters to be URL-encoded are encoded\nusing a `'%'` character and a two-character hex\nvalue corresponding to their UTF-8 character. For example,\n`上海+中國` in UTF-8 would be URL-encoded as\n`%E4%B8%8A%E6%B5%B7%2B%E4%B8%AD%E5%9C%8B`. The\nstring `? and the Mysterians` would be URL-encoded as\n`%3F+and+the+Mysterians` or `%3F%20and%20the%20Mysterians`.\n\nCommon characters that need encoding\n\nSome common characters that must be encoded are:\n\n| Unsafe character | Encoded value |\n|------------------|---------------|\n| Space | `%20` |\n| \" | `%22` |\n| \\\u003c | `%3C` |\n| \\\u003e | `%3E` |\n| # | `%23` |\n| % | `%25` |\n| \\| | `%7C` |\n\nConverting a URL that you receive from user input is sometimes\ntricky. For example, a user may enter an address as \"5th\\&Main St.\"\nGenerally, you should construct your URL from its parts, treating\nany user input as literal characters.\n\nAdditionally, URLs are limited to 16384 characters for all Google Maps Platform web services\nand static web APIs. For most services, this character limit will seldom be approached. However,\nnote that certain services have several parameters that may result in long URLs."]]
