49 lines
1.3 KiB
Markdown
49 lines
1.3 KiB
Markdown
# nlohmann::json_view
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Defined in header `<nlohmann/json_view.hpp>`
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```
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using json_view = basic_json_view<json, view_mode::read_only>;
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```
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This type is a [`basic_json_view`](https://json.nlohmann.me/api/basic_json_view/index.md) of a value of a [`json_document`](https://json.nlohmann.me/api/json_document/index.md).
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## Examples
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Example
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The example below demonstrates how to use the type `nlohmann::json_view`.
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```
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#include <iostream>
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#include <nlohmann/json_view.hpp>
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int main()
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{
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std::cout << std::boolalpha;
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// json_view is basic_json_view<nlohmann::json>: a read-only handle
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// returned by json_document::root()
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nlohmann::json_document doc = nlohmann::json_document::parse("[1, 2, 3]");
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nlohmann::json_view v = doc.root();
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std::cout << v.is_array() << ' ' << v.size() << '\n';
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}
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```
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Output:
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```
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true 3
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```
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## See also
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- [`json_document`](https://json.nlohmann.me/api/json_document/index.md) - the document type this view refers into
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- [`ordered_json_view`](https://json.nlohmann.me/api/ordered_json_view/index.md) - the corresponding view for `ordered_json_document`
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- [Zero-copy JSON views](https://json.nlohmann.me/features/json_view/index.md) - how to parse, inspect and edit a document without building a tree
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## Version history
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Added in version 3.13.0 unreleased.
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