本文章介紹了關於php中json_decode()和json_encode()用法與中文不顯示解決辦法，有需要的朋友可以參考一下下。
php中json_decode()和json_encode()
1.json_decode()
json_decode
(PHP 5 >= 5.2.0, PECL json >= 1.2.0)
json_decode — 對 JSON 格式的字符串進行編碼
說明
mixed json_decode ( string $json [, bool $assoc ] )
接受一個 JSON 格式的字符串並且把它轉換為 PHP 變量
參數
json
待解碼的 json string 格式的字符串。
assoc
當該參數為 TRUE 時，將返回 array 而非 object 。
返回值
Returns an object or if the optional assoc parameter is TRUE, an associative array is instead returned.
范例
Example #1 json_decode() 的例子
代碼如下 復制代碼<?php
$json = '{"a":1,"b":2,"c":3,"d":4,"e":5}';
var_dump(json_decode($json));
var_dump(json_decode($json, true));
?>
上例將輸出：
object(stdClass)#1 (5) {
["a"] => int(1)
["b"] => int(2)
["c"] => int(3)
["d"] => int(4)
["e"] => int(5)
}
array(5) {
["a"] => int(1)
["b"] => int(2)
["c"] => int(3)
["d"] => int(4)
["e"] => int(5)
}
$data='[{"Name":"a1","Number":"123","Contno":"000","QQNo":""},{"Name":"a1","Number":"123","Contno":"000","QQNo":""},{"Name":"a1","Number":"123","Contno":"000","QQNo":""}]';
echo json_decode($data);
結果為：
Array ( [0] => stdClass Object ( [Name] => a1 [Number] => 123 [Contno] => 000 [QQNo] => ) [1] => stdClass Object ( [Name] => a1 [Number] => 123 [Contno] => 000 [QQNo] => ) [2] => stdClass Object ( [Name] => a1 [Number] => 123 [Contno] => 000 [QQNo] => ) )
可以看出經過json_decode()編譯出來的是對象,現在輸出json_decode($data,true)試下
代碼如下 復制代碼echo json_decode($data,true);
結果：
Array ( [0] => Array ( [Name] => a1 [Number] => 123 [Contno] => 000 [QQNo] => ) [1] => Array ( [Name] => a1 [Number] => 123 [Contno] => 000 [QQNo] => ) [2] => Array ( [Name] => a1 [Number] => 123 [Contno] => 000 [QQNo] => ) )
可以看出 json_decode($data,true)輸出的一個關聯數組,由此可知json_decode($data）輸出的是對象,而json_decode("$arr",true)是把它強制生成PHP關聯數組.
2.json_encode()
json_encode
(PHP 5 >= 5.2.0, PECL json >= 1.2.0)
json_encode — 對變量進行 JSON 編碼
Report a bug 說明
string json_encode ( mixed $value [, int $options = 0 ] )
返回 value 值的 JSON 形式
Report a bug 參數
value
待編碼的 value ，除了resource 類型之外，可以為任何數據類型
該函數只能接受 UTF-8 編碼的數據
options
由以下常量組成的二進制掩碼： JSON_HEX_QUOT, JSON_HEX_TAG, JSON_HEX_AMP, JSON_HEX_APOS, JSON_NUMERIC_CHECK, JSON_PRETTY_PRINT, JSON_UNESCAPED_SLASHES, JSON_FORCE_OBJECT, JSON_UNESCAPED_UNICODE.
Report a bug 返回值
編碼成功則返回一個以 JSON 形式表示的 string 或者在失敗時返回 FALSE 。
Report a bug 更新日志
版本 說明
5.4.0 options 參數增加常量： JSON_PRETTY_PRINT, JSON_UNESCAPED_SLASHES, 和 JSON_UNESCAPED_UNICODE。
5.3.3 options 參數增加常量：JSON_NUMERIC_CHECK。
5.3.0 增加 options 參數.
Report a bug 范例
Example #1 A json_encode() 的例子
代碼如下 復制代碼<?php
$arr = array ('a'=>1,'b'=>2,'c'=>3,'d'=>4,'e'=>5);
echo json_encode($arr);
?>
以上例程會輸出：
{"a":1,"b":2,"c":3,"d":4,"e":5}
Example #2 json_encode() 函數中 options 參數的用法
<?php
$a = array('<foo>',"'bar'",'"baz"','&blong&', "xc3xa9");
echo "Normal: ", json_encode($a), "n";
echo "Tags: ", json_encode($a, JSON_HEX_TAG), "n";
echo "Apos: ", json_encode($a, JSON_HEX_APOS), "n";
echo "Quot: ", json_encode($a, JSON_HEX_QUOT), "n";
echo "Amp: ", json_encode($a, JSON_HEX_AMP), "n";
echo "Unicode: ", json_encode($a, JSON_UNESCAPED_UNICODE), "n";
echo "All: ", json_encode($a, JSON_HEX_TAG | JSON_HEX_APOS | JSON_HEX_QUOT | JSON_HEX_AMP | JSON_UNESCAPED_UNICODE), "nn";
$b = array();
echo "Empty array output as array: ", json_encode($b), "n";
echo "Empty array output as object: ", json_encode($b, JSON_FORCE_OBJECT), "nn";
$c = array(array(1,2,3));
echo "Non-associative array output as array: ", json_encode($c), "n";
echo "Non-associative array output as object: ", json_encode($c, JSON_FORCE_OBJECT), "nn";
$d = array('foo' => 'bar', 'baz' => 'long');
echo "Associative array always output as object: ", json_encode($d), "n";
echo "Associative array always output as object: ", json_encode($d, JSON_FORCE_OBJECT), "nn";
?>
以上例程會輸出：
Normal: ["<foo>","'bar'",""baz"","&blong&","u00e9"]
Tags: ["u003Cfoou003E","'bar'",""baz"","&blong&","u00e9"]
Apos: ["<foo>","u0027baru0027",""baz"","&blong&","u00e9"]
Quot: ["<foo>","'bar'","u0022bazu0022","&blong&","u00e9"]
Amp: ["<foo>","'bar'",""baz"","u0026blongu0026","u00e9"]
Unicode: ["<foo>","'bar'",""baz"","&blong&","é"]
All: ["u003Cfoou003E","u0027baru0027","u0022bazu0022","u0026blongu0026","é"]
Empty array output as array: []
Empty array output as object: {}
Non-associative array output as array: [[1,2,3]]
Non-associative array output as object: {"0":{"0":1,"1":2,"2":3}}
Associative array always output as object: {"foo":"bar","baz":"long"}
Associative array always output as object: {"foo":"bar","baz":"long"}
Example #3 連續與非連續數組示例
代碼如下 復制代碼<?php
echo "連續數組".PHP_EOL;
$sequential = array("foo", "bar", "baz", "blong");
var_dump(
$sequential,
json_encode($sequential)
);
echo PHP_EOL."非連續數組".PHP_EOL;
$nonsequential = array(1=>"foo", 2=>"bar", 3=>"baz", 4=>"blong");
var_dump(
$nonsequential,
json_encode($nonsequential)
);
echo PHP_EOL."刪除一個連續數組值的方式產生的非連續數組".PHP_EOL;
unset($sequential[1]);
var_dump(
$sequential,
json_encode($sequential)
);
?>
以上例程會輸出：
代碼如下 復制代碼連續數組
array(4) {
[0]=>
string(3) "foo"
[1]=>
string(3) "bar"
[2]=>
string(3) "baz"
[3]=>
string(5) "blong"
}
string(27) "["foo","bar","baz","blong"]"
非連續數組
array(4) {
[1]=>
string(3) "foo"
[2]=>
string(3) "bar"
[3]=>
string(3) "baz"
[4]=>
string(5) "blong"
}
string(43) "{"1":"foo","2":"bar","3":"baz","4":"blong"}"
刪除一個連續數組值的方式產生的非連續數組
array(3) {
[0]=>
string(3) "foo"
[2]=>
string(3) "baz"
[3]=>
string(5) "blong"
}
string(33) "{"0":"foo","2":"baz","3":"blong"}"
$obj->Name= 'a1';$obj->Number ='123';
$obj->Contno= '000';
echo json_encode($obj);
結果為：
{"Name":"a1",
"Number":"123",
"Contno":"000"
}
可以看出json_encode()和json_decode()是編譯和反編譯過程，注意json只接受utf-8編碼的字符，所以json_encode()的參數必須是utf-8編碼，否則會得到空字符或者null
如果是中文的話就要注意了
在網上找到一種解決方法：
代碼如下 復制代碼<?php
/* 處理json_encode中文亂碼 */
$data = array ('game' => '冰火國度', 'name' => '刺之靈', 'country' => '冰霜國', 'level' => 45 );
echo json_encode ( $data );
echo "<br>";
$newData = array ();
foreach ( $data as $key => $value ) {
$newData [$key] = urlencode ( $value );
}
echo urldecode ( json_encode ( $newData ) );
?>
後來請教了別人，還可以用base64編碼，不過base64編碼不可以放在URL中，百度是這樣解釋的：
標准的Base64並不適合直接放在URL裡傳輸，因為URL編碼器會把標准Base64中的“/”和“+”字符變為形如“%XX”的形式，而這些“%”號在存入數據庫時還需要再進行轉換，因為ANSI SQL中已將“%”號用作通配符。
不過我的數據是要通過POST發送的，並不在HTTP 的head中，而在message-body裡，所以不受影響。
json_encode 只能接受utf-8格式的數據
例如：'胥'經過json_encode處理後變為'u80e5'，最終的json中中文部分被替換為unicode編碼。我們要解決的就是將對象轉換為json並保證對象內部的中文在json中仍然是以正常的中文出現，現在看來只使用json_encode是不能達到目的的。
我的解決方法：先將類中的中文字段進行url編碼（urlencode），然後再對對象進行json編碼（jsonencode），最後url解碼（urldecode）json，即最終的json，裡面的中文依舊是那個中文！
測試代碼如下：
<?php
class myClass {
public $item1 = 1;
public $item2 = '中文';
function to_json() {
//url編碼,避免json_encode將中文轉為unicode
$this->item2 = urlencode($this->item2);
$str_json = json_encode($this);
//url解碼,轉完json後將各屬性返回,確保對象屬性不變
$this->item2 = urldecode($this->item2);
return urldecode($str_json);
}
}
$c = new myClass();
echo json_encode($c);
echo '<br/>';
echo $c->to_json();
echo '<br/>';
echo json_encode($c);
echo '<br/>';
echo json_encode('胥');
?>
程序輸出結果：
{"item1":1,"item2":"u4e2du6587"}
{"item1":1,"item2":"中文"}
{"item1":1,"item2":"u4e2du6587"}
"u80e5"
