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📜  Prototype-哈希处理

📅  最后修改于: 2020-10-21 08:45:14             🧑  作者: Mango

 

哈希可以看作是将唯一键绑定到值的关联数组。唯一的区别是您可以将任何字符串用作索引，而不仅仅是将数字用作索引。

创建哈希

构造Hash实例有两种方法-

  • 使用JavaScript关键字new 。
  • 使用原型工具函数$ H。

要创建一个空哈希，您也可以调用任何不带参数的构造方法。

以下是显示如何以简单方式创建哈希，设置值和获取值的示例-

// Creating Hash
var myhash = new Hash();
var yourhash = new Hash( {fruit: 'apple'} );
var hishash = $H( {drink: 'pepsi'} );

// Set values in terms of key and values.
myhash.set('name', 'Bob');

// Get value of key 'name' as follows.
myhash.get('name');
yourhash.get('fruit');
hishash.get('drink');

// Unset a key & value
myhash.unset('name');
yourhash.unset('fruit');
hishash.unset('drink');

原型提供了广泛的方法来轻松评估哈希。本教程将通过适当的示例详细解释每种方法。

这是与哈希相关的所有方法的完整列表。

Prototype哈希方法

注意-确保至少具有1.6版的prototype.js。

S.No. Method & Description
1. clone()

Returns a clone of hash.
2. each()

Iterates over the name/value pairs in the hash.
3. get()

Returns the value of the hash key’s property.
4. inspect()

Returns the debug-oriented string representation of the hash.
5. keys()

Provides an Array of keys (that is, property names) for the hash.
6. merge()

Merges object to hash and returns the result of that merge.
7. remove()

Removes keys from a hash and returns their values. This method has been deprecated in version 1.6.
8. set()

Sets the hash key’s property to value and returns value.
9. toJSON()

Returns a JSON string.
10. toObject()

Returns a cloned, vanilla object.
11. toQueryString()

Turns a hash into its URL-encoded query string representation.
12. unset()

Deletes the hash key’s property and returns its value.
13. update()

Updates hash with the key/value pairs of object. The original hash will be modified.
14. values()

Collects the values of a hash and returns them in an array.