{"id":1564,"date":"2020-10-30T20:14:37","date_gmt":"2020-10-30T16:44:37","guid":{"rendered":"https:\/\/behnudi.ir\/?p=1564"},"modified":"2024-09-04T11:38:38","modified_gmt":"2024-09-04T08:08:38","slug":"js05-expression","status":"publish","type":"post","link":"https:\/\/behnudi.ir\/?p=1564","title":{"rendered":"\u062c\u0627\u0648\u0627\u0633\u06a9\u0631\u06cc\u067e\u062a: \u06f5- \u0627\u06a9\u0633\u067e\u0631\u0634\u0646"},"content":{"rendered":"<h2>\u0627\u0650\u06a9\u0633\u067e\u0631\u0650\u0634\u0646 &#8211; Expression<\/h2>\n<p>\u062a\u0635\u0648\u06cc\u0631 \u0632\u06cc\u0631 \u0631\u0627 \u0628\u0628\u06cc\u0646\u06cc\u062f \u0648 \u0628\u0627 \u0686\u0646\u062f \u0627\u0635\u0637\u0644\u0627\u062d \u0622\u0634\u0646\u0627 \u0634\u0648\u06cc\u062f.<\/p>\n<p><img decoding=\"async\" class=\"aligncenter wp-image-813\" src=\"https:\/\/behnudi.ir\/f\/js1\/05\/img\/operator.png\" \/><\/p>\n<ul>\n<li><strong>\u0627\u0650\u06a9\u0633\u067e\u0631\u0650\u0634\u0646 (Expression):<\/strong> \u0642\u0637\u0639\u0647\u200c\u0627\u06cc \u0627\u0632 \u06a9\u062f \u06a9\u0647 \u0639\u0645\u0644\u06cc\u0627\u062a\u06cc \u06cc\u0627 \u0645\u062d\u0627\u0633\u0628\u0627\u062a\u06cc \u0631\u0627 \u0627\u0646\u062c\u0627\u0645 \u0645\u06cc \u062f\u0647\u062f \u062a\u0627 \u06cc\u06a9 \u0645\u0642\u062f\u0627\u0631 \u0631\u0627 \u0628\u062f\u0633\u062a \u0622\u0648\u0631\u062f.<\/li>\n<li><strong>\u0622\u067e\u0650\u0631\u0650\u06cc\u062a\u0648\u0631 (Operator):<\/strong> \u06cc\u0627 \u0639\u0645\u0644\u06af\u0631 \u0645\u062b\u0644 \u062c\u0645\u0639 \u06cc\u0627 \u0636\u0631\u0628 \u0639\u0645\u0644\u06cc \u0627\u0633\u062a \u06a9\u0647 \u0631\u0648\u06cc \u0645\u0642\u0627\u062f\u06cc\u0631 \u0627\u0646\u062c\u0627\u0645 \u0645\u06cc\u200c\u06af\u06cc\u0631\u062f \u0648 \u0646\u062a\u06cc\u062c\u0647\u200c\u0627\u06cc \u0628\u0647 \u062f\u0633\u062a \u0645\u06cc\u200c\u0622\u06cc\u062f.<\/li>\n<li><strong>\u0622\u067e\u0650\u0631\u064e\u0646\u062f (Operand):<\/strong> \u06cc\u0627 \u0639\u0645\u0644\u0648\u0646\u062f \u0645\u0642\u0627\u062f\u06cc\u0631 \u0627\u0648\u0644\u06cc\u0647\u200c\u0627\u06cc \u0647\u0633\u062a\u0646\u062f \u06a9\u0647 \u0639\u0645\u0644\u06cc\u0627\u062a \u0631\u0648\u06cc \u0622\u0646\u0647\u0627 \u0627\u0646\u062c\u0627\u0645 \u0645\u06cc\u200c\u0634\u0648\u062f.<\/li>\n<\/ul>\n<h3>\u0622\u067e\u0631\u06cc\u062a\u0648\u0631\u0647\u0627\u06cc \u0627\u0633\u062a\u0631\u06cc\u0646\u06af<\/h3>\n<p><strong>\u067e\u06cc\u0648\u0633\u062a\u0646<\/strong><\/p>\n<pre><code class=\"js\">\r\na = \"my\" + \"String\"; \/\/ myString    Concatenate\r\n\r\n<\/code><\/pre>\n<p>\u0645\u0642\u0627\u062f\u06cc\u0631 \u0628\u0627 \u0646\u0648\u0639 \u0645\u062a\u0641\u0627\u0648\u062a \u0631\u0627 \u0628\u0647 \u0627\u0633\u062a\u0631\u06cc\u0646\u06af \u062a\u0628\u062f\u06cc\u0644 \u0645\u06cc\u200c\u06a9\u0646\u062f.<\/p>\n<pre><code class=\"js\">\r\na = \"5\" + 2;            \/\/ \"52\"\r\n\r\na = 2 + \"5\";            \/\/ \"25\"\r\n\r\na = \"5\" + 2 + 1;        \/\/ \"521\"\r\n\r\na = 2 + 1 + \"5\";        \/\/ \"35\"\r\n\r\na = true + \"5\";         \/\/ \"true5\"\r\n\r\na = false + \"5\";        \/\/ \"false5\"\r\n\r\na = null + \"5\";         \/\/ \"null5\"\r\n\r\na = undefined + \"5\";    \/\/ \"undefined5\"\r\n\r\na = Infinity + \"5\";     \/\/ \"Infinity5\"\r\n\r\na = NaN + \"5\";          \/\/ \"NaN5\"\r\n\r\n<\/code><\/pre>\n<hr \/>\n<p><video controls=\"controls\"><source src=\"https:\/\/behnudi.ir\/f\/js1\/05\/js1051.mp4\" type=\"video\/mp4\" \/>Your browser does not support the video tag.<\/video><\/p>\n<hr \/>\n<h4>\u062a\u0645\u0631\u06cc\u0646 \u06f1<\/h4>\n<ul>\n<li>\u0627\u06cc\u0646 <a href=\"https:\/\/behnudi.ir\/f\/js1\/05\/05-1.zip\">\u0641\u0627\u06cc\u0644<\/a>\u00a0\u0631\u0627 \u062f\u0627\u0646\u0644\u0648\u062f \u06a9\u0646\u06cc\u062f.<\/li>\n<li>\u0622\u0646 \u0631\u0627 \u062f\u0631 \u0641\u0648\u0644\u062f\u0631 js1 \u0628\u0627\u0632 \u06a9\u0646\u06cc\u062f.<\/li>\n<li>\u062a\u0646\u0647\u0627 \u0641\u0627\u06cc\u0644 script.js \u0631\u0627 \u0645\u06cc\u200c\u062a\u0648\u0627\u0646\u06cc\u062f \u062a\u063a\u06cc\u06cc\u0631 \u062f\u0647\u06cc\u062f.<\/li>\n<li>\u0647\u0631\u06af\u0627\u0647 \u0631\u0648\u06cc \u062f\u06a9\u0645\u0647 + \u06a9\u0644\u06cc\u06a9 \u0634\u062f\u060c \u0645\u0642\u062f\u0627\u0631 \u062f\u0648 \u062e\u0627\u0646\u0647 \u0627\u0648\u0644 \u0648 \u062f\u0648\u0645 \u0631\u0627 \u067e\u0634\u062a \u0647\u0645 \u062f\u0631 \u062e\u0627\u0646\u0647 \u0633\u0648\u0645 \u0628\u0646\u0648\u06cc\u0633\u062f.<\/li>\n<\/ul>\n<p><img decoding=\"async\" class=\"aligncenter size-full wp-image-814\" src=\"https:\/\/behnudi.ir\/f\/js1\/05\/img\/05-1.png\" \/><\/p>\n<hr \/>\n<h3>\u0622\u067e\u0631\u06cc\u062a\u0648\u0631\u0647\u0627\u06cc \u062d\u0633\u0627\u0628<\/h3>\n<p><strong>\u0633\u0627\u062f\u0647<\/strong><\/p>\n<pre><code class=\"js\">\r\na = 1 + 2;    \/\/ 3    Addition\r\n\r\na = 5 - 2;    \/\/ 3    Subtraction\r\n\r\na = 2 * 3;    \/\/ 6    Multiplication\r\n\r\na = 6 \/ 2;    \/\/ 3    Division\r\n\r\na = 5 % 3;    \/\/ 2    Modulus\r\n\r\na = 2 ** 3;   \/\/ 8   Exponentiation    \r\n\r\n<\/code><\/pre>\n<p>\u0645\u0642\u0627\u062f\u06cc\u0631 \u0628\u0627 \u0646\u0648\u0639 \u0645\u062a\u0641\u0627\u0648\u062a \u0631\u0627 \u0628\u0647 \u0639\u062f\u062f \u062a\u0628\u062f\u06cc\u0644 \u0645\u06cc\u200c\u06a9\u0646\u062f.<\/p>\n<pre><code class=\"js\">\r\na = +\"1\" + +\"2\";      \/\/ 3\r\n\r\na = \"5\" - \"3\";        \/\/ 2\r\n\r\na = \"2\" * \"3\";        \/\/ 6\r\n\r\na = \"6\" \/ \"2\";        \/\/ 3\r\n\r\na = \"5\" % \"3\";        \/\/ 2\r\n\r\na = \"2\" ** \"3\";       \/\/ 8\r\n\r\na = true + true;      \/\/ 2\r\n\r\na = 3 - true;         \/\/ 2\r\n\r\na = false * 5;        \/\/ 0\r\n\r\na = 5 ** false;       \/\/ 1\r\n\r\na = 2 + null;         \/\/ 2\r\n\r\na = 2 + undefined;    \/\/ NaN\r\n\r\n<\/code><\/pre>\n<hr \/>\n<p><video controls=\"controls\"><source src=\"https:\/\/behnudi.ir\/f\/js1\/05\/js1052.mp4\" type=\"video\/mp4\" \/>Your browser does not support the video tag.<\/video><\/p>\n<hr \/>\n<h4>\u062a\u0645\u0631\u06cc\u0646 \u06f2<\/h4>\n<ul>\n<li>\u0627\u06cc\u0646 <a href=\"https:\/\/behnudi.ir\/f\/js1\/05\/05-2.zip\" download>\u0641\u0627\u06cc\u0644<\/a>\u00a0\u0631\u0627 \u062f\u0627\u0646\u0644\u0648\u062f \u06a9\u0646\u06cc\u062f.<\/li>\n<li>\u0622\u0646 \u0631\u0627 \u062f\u0631 \u0641\u0648\u0644\u062f\u0631 js1 \u0628\u0627\u0632 \u06a9\u0646\u06cc\u062f.<\/li>\n<li>\u062a\u0646\u0647\u0627 \u0641\u0627\u06cc\u0644 script.js \u0631\u0627 \u0645\u06cc\u200c\u062a\u0648\u0627\u0646\u06cc\u062f \u062a\u063a\u06cc\u06cc\u0631 \u062f\u0647\u06cc\u062f.<\/li>\n<li>\u0647\u0631\u06af\u0627\u0647 \u0631\u0648\u06cc \u062f\u06a9\u0645\u0647\u200c\u0647\u0627 \u06a9\u0644\u06cc\u06a9 \u0634\u062f\u060c \u062d\u0627\u0635\u0644 \u0639\u0645\u0644 \u0631\u0648\u06cc \u062e\u0627\u0646\u0647 \u0627\u0648\u0644 \u0648 \u062f\u0648\u0645 \u0631\u0627 \u062f\u0631 \u062e\u0627\u0646\u0647 \u0633\u0648\u0645 \u0628\u0646\u0648\u06cc\u0633\u062f.<\/li>\n<\/ul>\n<p><img decoding=\"async\" class=\"aligncenter size-full wp-image-814\" src=\"https:\/\/behnudi.ir\/f\/js1\/05\/img\/05-2.png\" \/><\/p>\n<hr \/>\n<p><b>\u062a\u06a9 \u0622\u067e\u0631\u0646\u062f<\/b><\/p>\n<pre><code class=\"js\">\r\na = 2;    ++a;    \/\/ a = 3;    a = a + 1;    Pre-Increment \r\n\r\na = 2;    a++;    \/\/ a = 3;    a = a + 1;    Post-Increment \r\n\r\na = 2;    --a;    \/\/ a = 1;    a = a - 1;    Pre-Decrement\r\n\r\na = 2;    a--;    \/\/ a = 1;    a = a - 1;    Post-Decrement\r\n\r\n\/\/=========================================================\r\n\r\na = 2;    b = 5 + ++a;    \/\/ a = 3; b = 8;    b = 5 + (a + 1);\r\n\r\na = 2;    b = 5 + a++;    \/\/ a = 3; b = 7;    b = 5 + a;\r\n\r\na = 2;    b = 5 + --a;    \/\/ a = 1; b = 6;    b = 5 + (a - 1);\r\n\r\na = 2;    b = 5 + a--;    \/\/ a = 1; b = 7;    b = 5 + a;\r\n\r\n<\/code><\/pre>\n<p><b>\u0645\u062d\u0627\u0633\u0628\u0647 \u062f\u0631\u062c\u0627<\/b><\/p>\n<pre><code class=\"js\">\r\na = 6;    a += 2;          \/\/ a = 8;             a = a + 2;\r\n\r\na = 6;    a -= 2;          \/\/ a = 4;             a = a - 2;\r\n\r\na = 6;    a *= 2;          \/\/ a = 12;            a = a * 2;\r\n\r\na = 6;    a \/= 2;          \/\/ a = 3;             a = a \/ 2;\r\n\r\na = 5;    a %= 2;          \/\/ a = 1;             a = a % 2;\r\n\r\na = 2;    a **= 3;         \/\/ a = 8;             a = a ** 3;\r\n\/\/---------------------------------------------------------------\r\na = \"my\"; a += \"String\"    \/\/ a = \"myString\";    a = a + \"String\";\r\n\r\n<\/code><\/pre>\n<h3>\u0622\u067e\u0631\u06cc\u062a\u0648\u0631\u0647\u0627\u06cc \u0628\u0648\u0644\u06cc\u064e\u0646<\/h3>\n<p><b>\u0633\u0627\u062f\u0647<\/b><\/p>\n<pre><code class=\"js\">\/\/ And ----------------------------------\r\na = true &amp;&amp; true;           \/\/ a = true;\r\n\r\na = true &amp;&amp; false;          \/\/ a = false;\r\n\r\na = false &amp;&amp; true;          \/\/ a = false;\r\n\r\na = false &amp;&amp; false;         \/\/ a = false;\r\n\/\/ Or -----------------------------------\r\na = true || true;           \/\/ a = true;\r\n\r\na = true || false;          \/\/ a = true;\r\n\r\na = false || true;          \/\/ a = true;\r\n\r\na = false || false;         \/\/ a = false;\r\n\/\/ Not ----------------------------------\r\na = ! true;                 \/\/ a = false;\r\n\r\na = ! false;                \/\/ a = true;\r\n\r\n<\/code><\/pre>\n<p>\u0645\u0642\u0627\u062f\u06cc\u0631 \u0628\u0627 \u0646\u0648\u0639 \u0645\u062a\u0641\u0627\u0648\u062a \u0631\u0627 \u0628\u0647 \u0628\u0648\u0644\u06cc\u0646 \u062a\u0628\u062f\u06cc\u0644 \u0645\u06cc\u200c\u06a9\u0646\u062f.<\/p>\n<pre><code class=\"js\">\r\n\/\/ And -----------------------------------\r\na = true &amp;&amp; 5;                \/\/ a = 5;\r\na = true &amp;&amp; \"Str\";            \/\/ a = \"Str\";\r\n\r\na = false &amp;&amp; 5;               \/\/ a = false;\r\na = false &amp;&amp; \"Str\";           \/\/ a = false;\r\n\/\/ Or ------------------------------------\r\na = true || 5;                \/\/ a = true;\r\na = true || \"Str\";            \/\/ a = true;\r\n\r\na = false || 5;               \/\/ a = 5;\r\na = false || \"Str\";           \/\/ a = \"Str\";\r\n\/\/ Not -----------------------------------\r\na = ! 0;                      \/\/ a = true;\r\na = ! 5;                      \/\/ a = false; Any non-zero number\r\n\r\na = ! \"\";                     \/\/ a = true;\r\na = ! \" \";                    \/\/ a = false; Any non-zero string\r\n\r\na = ! null;                   \/\/ a = true;\r\na = ! undefined;              \/\/ a = true;\r\na = ! NaN;                    \/\/ a = true;\r\n\r\n<\/code><\/pre>\n<hr \/>\n<p><video controls=\"controls\"><source src=\"https:\/\/behnudi.ir\/f\/js1\/05\/js1053.mp4\" type=\"video\/mp4\" \/>Your browser does not support the video tag.<\/video><\/p>\n<hr \/>\n<h4>\u062a\u0645\u0631\u06cc\u0646 \u06f3<\/h4>\n<ul>\n<li>\u0627\u06cc\u0646 <a href=\"https:\/\/behnudi.ir\/f\/js1\/05\/05-3.zip\" download>\u0641\u0627\u06cc\u0644<\/a>\u00a0\u0631\u0627 \u062f\u0627\u0646\u0644\u0648\u062f \u06a9\u0646\u06cc\u062f.<\/li>\n<li>\u0622\u0646 \u0631\u0627 \u062f\u0631 \u0641\u0648\u0644\u062f\u0631 js1 \u0628\u0627\u0632 \u06a9\u0646\u06cc\u062f.<\/li>\n<li>\u062a\u0646\u0647\u0627 \u0641\u0627\u06cc\u0644 script.js \u0631\u0627 \u0645\u06cc\u200c\u062a\u0648\u0627\u0646\u06cc\u062f \u062a\u063a\u06cc\u06cc\u0631 \u062f\u0647\u06cc\u062f.<\/li>\n<li>\u0647\u0631\u06af\u0627\u0647 \u0631\u0648\u06cc \u062f\u06a9\u0645\u0647\u200c\u0647\u0627 \u06a9\u0644\u06cc\u06a9 \u0634\u062f\u060c \u062d\u0627\u0635\u0644 \u0639\u0645\u0644 \u0631\u0648\u06cc \u062e\u0627\u0646\u0647 \u0627\u0648\u0644 \u0648 \u062f\u0648\u0645 \u0631\u0627 \u062f\u0631 \u062e\u0627\u0646\u0647 \u0633\u0648\u0645 \u0628\u0646\u0648\u06cc\u0633\u062f.<\/li>\n<\/ul>\n<p><img decoding=\"async\" class=\"aligncenter size-full wp-image-814\" src=\"https:\/\/behnudi.ir\/f\/js1\/05\/img\/05-3.png\" \/><\/p>\n<hr \/>\n<h3>\u0622\u067e\u0631\u06cc\u062a\u0648\u0631\u0647\u0627\u06cc \u0645\u0642\u0627\u06cc\u0633\u0647\u200c<\/h3>\n<p><strong>\u0645\u0642\u0627\u06cc\u0633\u0647 \u0639\u062f\u062f\u0647\u0627<\/strong><\/p>\n<pre><code class=\"js\">\r\nr = 2 == 2;    \/\/ r = true;    Equal to\r\n\r\nr = 2 != 2;    \/\/ r = false;   Not Equal\r\n\r\nr = 2 &lt; 3;     \/\/ r = true;    Less than\r\n\r\nr = 2 &gt; 2;     \/\/ r = false;   Greater than\r\n\r\nr = 2 &lt;= 2;    \/\/ r = true;    Less than or Equal to\r\n\r\nr = 2 &gt;= 3;    \/\/ r = false;   Greater than or Equal to\r\n\r\n<\/code><\/pre>\n<p><strong>\u0645\u0642\u0627\u06cc\u0633\u0647 \u0627\u0633\u062a\u0631\u06cc\u0646\u06af\u200c\u0647\u0627<\/strong><\/p>\n<pre><code class=\"js\">\r\nr = \"B\" == \"B\";    \/\/ r = true;     Equal to\r\n\r\nr = \"B\" != \"B\";    \/\/ r = false;    Not Equal\r\n\r\nr = \"B\" &lt; \"C\";     \/\/ r = true;     Less than\r\n\r\nr = \"B\" &gt; \"B\";     \/\/ r = false;    Greater than\r\n\r\nr = \"B\" &lt;= \"B\";    \/\/ r = true;     Less than or Equal to \r\n\r\nr = \"B\" &gt;= \"C\";    \/\/ r = false;    Greater than or Equal to\r\n\r\n<\/code><\/pre>\n<p><img decoding=\"async\" src=\"https:\/\/behnudi.ir\/f\/js1\/05\/img\/ASCII-Table.svg\" \/><br \/>\n<strong>\u0645\u0642\u0627\u06cc\u0633\u0647 \u0628\u0648\u0644\u06cc\u0646<\/strong><\/p>\n<pre><code class=\"js\">\r\nr = true == true;     \/\/ r = true;     Equal to\r\n\r\nr = true != true;     \/\/ r = false;    Not Equal\r\n\r\nr = false &lt; true;     \/\/ r = true;     Less than\r\n\r\nr = false &gt; true;     \/\/ r = false;    Greater than\r\n\r\nr = false &lt;= false;   \/\/ r = true;     Less than or Equal to\r\n\r\nr = false &gt;= true;    \/\/ r = false;    Greater than or Equal to\r\n\r\n<\/code><\/pre>\n<p>\u0645\u0642\u0627\u06cc\u0633\u0647 \u0645\u0642\u0627\u062f\u06cc\u0631 \u0628\u0627 \u0646\u0648\u0639 \u0645\u062a\u0641\u0627\u0648\u062a \u0631\u0627 \u0628\u0647 \u0639\u062f\u062f \u062a\u0628\u062f\u06cc\u0644 \u0645\u06cc\u200c\u06a9\u0646\u062f.<\/p>\n<pre><code class=\"js\">\r\nr = \"002\" == 2;     \/\/ r = true;      \"002\" -&gt; 2\r\n\r\nr = \"2\" != 2;       \/\/ r = false;     \"2\" -&gt; 2\r\n\r\nr = \"2\" &lt; 3;        \/\/ r = true;      \"2\" -&gt; 2\r\n\r\nr = \"2\" &gt; 2;        \/\/ r = false;     \"2\" -&gt; 2\r\n\r\nr = \"02\" &lt;= 2;      \/\/ r = true;      \"02\" -&gt; 2\r\n\r\nr = \"2\" &gt;= 3;       \/\/ r = false;     \"2\" -&gt; 2\r\n\r\nr = \"\" == 0;        \/\/ r = true;      \"\" -&gt; 0\r\n\r\nr = false == \"\";    \/\/ r = true;      false -&gt; 0, \"\" -&gt; 0\r\n\r\nr = false == \"0\";   \/\/ r = true;      false -&gt; 0, \"0\" -&gt; 0\r\n\r\nr = true == \"1\";    \/\/ r = true;      true -&gt; 1, \"1\" -&gt; 1\r\n\r\n<\/code><\/pre>\n<hr \/>\n<p><video controls=\"controls\"><source src=\"https:\/\/behnudi.ir\/f\/js1\/05\/js1054.mp4\" type=\"video\/mp4\" \/>Your browser does not support the video tag.<\/video><\/p>\n<hr \/>\n<h4>\u062a\u0645\u0631\u06cc\u0646 \u06f4<\/h4>\n<ul>\n<li>\u0627\u06cc\u0646 <a href=\"https:\/\/behnudi.ir\/f\/js1\/05\/05-4.zip\" download>\u0641\u0627\u06cc\u0644<\/a>\u00a0\u0631\u0627 \u062f\u0627\u0646\u0644\u0648\u062f \u06a9\u0646\u06cc\u062f.<\/li>\n<li>\u0622\u0646 \u0631\u0627 \u062f\u0631 \u0641\u0648\u0644\u062f\u0631 js1 \u0628\u0627\u0632 \u06a9\u0646\u06cc\u062f.<\/li>\n<li>\u062a\u0646\u0647\u0627 \u0641\u0627\u06cc\u0644 script.js \u0631\u0627 \u0645\u06cc\u200c\u062a\u0648\u0627\u0646\u06cc\u062f \u062a\u063a\u06cc\u06cc\u0631 \u062f\u0647\u06cc\u062f.<\/li>\n<li>\u0647\u0631\u06af\u0627\u0647 \u0631\u0648\u06cc \u062f\u06a9\u0645\u0647\u200c\u0647\u0627 \u06a9\u0644\u06cc\u06a9 \u0634\u062f\u060c \u062d\u0627\u0635\u0644 \u0639\u0645\u0644 \u0631\u0648\u06cc \u062e\u0627\u0646\u0647 \u0627\u0648\u0644 \u0648 \u062f\u0648\u0645 \u0631\u0627 \u062f\u0631 \u062e\u0627\u0646\u0647 \u0633\u0648\u0645 \u0628\u0646\u0648\u06cc\u0633\u062f.<\/li>\n<\/ul>\n<p><img decoding=\"async\" class=\"aligncenter size-full wp-image-814\" src=\"https:\/\/behnudi.ir\/f\/js1\/05\/img\/05-4.png\" \/><\/p>\n<hr \/>\n<p><b>\u0645\u0642\u0627\u06cc\u0633\u0647 <mark>null<\/mark><\/b><\/p>\n<pre><code class=\"js\">\r\n\/\/ null equal to\r\n\r\nr = null == null;         \/\/ r = true;\r\n\r\nr = null == undefined;    \/\/ r = true;\r\n\r\n\/\/ null not-equal to\r\n\r\nr = null != 0;            \/\/ r = true;\r\n\r\nr = null != \"\";           \/\/ r = true;\r\n\r\nr = null != false;        \/\/ r = true;\r\n\r\n\/\/ null vs 0, \"\", false\r\n\r\nr = null == 0;            \/\/ r = false;\r\n\r\nr = null &lt; 0;             \/\/ r = false;\r\n\r\nr = null &gt; 0;             \/\/ r = false;\r\n<mark>\r\nr = null &lt;= 0;            \/\/ r = true;\r\n\r\nr = null &gt;= 0;            \/\/ r = true;\r\n<\/mark>\r\nr = null != 0;            \/\/ r = true;\r\n\r\n<\/code><\/pre>\n<p><b>\u0645\u0642\u0627\u06cc\u0633\u0647 <mark>undefined<\/mark><\/b><\/p>\n<pre><code class=\"js\">\r\n\/\/ undefined equal to\r\nr = undefined == null;            \/\/ r = true;\r\n\r\nr = undefined == undefined;       \/\/ r = true;\r\n\r\n\/\/ undefined not-equal to\r\n\r\nr = undefined != 0;               \/\/ r = true;\r\n\r\nr = undefined != \"\";              \/\/ r = true;\r\n\r\nr = undefined != false;           \/\/ r = true;\r\n\r\n\/\/ undefined vs 0, \"\", false\r\n\r\nr = undefined == 0;               \/\/ r = false;\r\n\r\nr = undefined &lt; 0;                \/\/ r = false;\r\n\r\nr = undefined &gt; 0;                \/\/ r = false;\r\n\r\nr = undefined &lt;= 0;               \/\/ r = false;\r\n\r\nr = undefined &gt;= 0;               \/\/ r = false;\r\n\r\nr = undefined != 0;               \/\/ r = true;\r\n\r\n<\/code><\/pre>\n<p><b>\u0645\u0642\u0627\u06cc\u0633\u0647 <mark>NaN<\/mark><\/b><\/p>\n<pre><code class=\"js\">\r\n\r\n\/\/ NaN not-equal to anything.\r\n\r\nr = NaN != 0;            \/\/ r = true;\r\n\r\nr = NaN != \"\";           \/\/ r = true;\r\n\r\nr = NaN != false;        \/\/ r = true;\r\n\r\nr = NaN != null;         \/\/ r = true;\r\n\r\nr = NaN != undefined;    \/\/ r = true;\r\n<mark>\r\nr = NaN != NaN;          \/\/ r = true;<\/mark>\r\n\r\n\/\/ x is whatever\r\n\r\nr = NaN == x;            \/\/ r = false;\r\n\r\nr = NaN &lt; x; \/\/ r = false; r = NaN &gt; x;             \/\/ r = false;\r\n\r\nr = NaN &lt;= x; \/\/ r = false; r = NaN &gt;= x;            \/\/ r = false;\r\n<mark>\r\nr = NaN != x;            \/\/ r = true;<\/mark>\r\n\r\n<\/code><\/pre>\n<p><strong>\u0645\u0642\u0627\u06cc\u0633\u0647 \u0646\u0648\u0639 \u0648 \u0645\u0642\u062f\u0627\u0631<\/strong><\/p>\n<pre><code class=\"js\">\r\nr = \"2\" == 2;            \/\/ r = true;         Value\r\n\r\nr = \"2\" === 2;           \/\/ r = false;        Value &amp; type\r\n\/\/-------------------------------------------------------\r\nr = \"2\" != 2;            \/\/ r = false;        Value\r\n\r\nr = \"2\" !== 2;           \/\/ r = true;         Value &amp; Type\r\n\/\/-------------------------------------------------------\r\nr = true !== 1;          \/\/ r = true;         Value &amp; Type\r\n\r\nr = false !== 0;         \/\/ r = true;         Value &amp; Type\r\n\/\/-------------------------------------------------------\r\nr = null !== undefined;  \/\/ r = true;         Value &amp; Type \r\n\r\n<\/code><\/pre>\n<h3>TL;DR<\/h3>\n<ol>\n<li><mark>\u062a\u0628\u062f\u06cc\u0644 \u0628\u0647 \u0639\u062f\u062f:<\/mark> \u0647\u0645\u0647 \u0622\u067e\u0631\u06cc\u062a\u0648\u0631\u0647\u0627<\/li>\n<li><mark>\u062a\u0628\u062f\u06cc\u0644 \u0628\u0647 \u0627\u0633\u062a\u0631\u06cc\u0646\u06af:<\/mark> \u0622\u067e\u0631\u06cc\u062a\u0648\u0631 + \u0627\u06af\u0631 \u06cc\u06a9 \u0627\u0632 \u0622\u067e\u0631\u0646\u062f\u0647\u0627\u06cc\u0634 \u0627\u0633\u062a\u0631\u06cc\u0646\u06af \u0628\u0627\u0634\u062f.<\/li>\n<li><mark>\u062a\u0628\u062f\u06cc\u0644 \u0628\u0647 \u0628\u0648\u0644\u06cc\u0646:<\/mark> \u0622\u067e\u0631\u06cc\u062a\u0648\u0631 \u0628\u0648\u0644\u06cc\u0646<\/li>\n<li><mark>null == undefined<\/mark><\/li>\n<li><mark>NaN<\/mark> \u0628\u0627 \u0647\u06cc\u0686 \u0686\u06cc\u0632\u06cc \u0645\u0633\u0627\u0648\u06cc \u0646\u06cc\u0633\u062a.<\/li>\n<\/ol>\n<h3>\u0627\u0644\u0648\u06cc\u062a \u0622\u067e\u0631\u06cc\u062a\u0648\u0631\u0647\u0627<\/h3>\n<pre><code class=\"js\">\r\n 1        ( )\r\n 2        ++ --\r\n 3        **\r\n 4        * \/ %\r\n 5        + -\r\n 6        &lt; &gt; &lt;= &gt;=\r\n 7        == != === !==\r\n 8        &amp;&amp;\r\n 9        ||\r\n10        = += -= *= \/= %=\r\n\r\n<\/code><\/pre>\n<hr \/>\n<h3>Number<\/h3>\n<p>\u0622\u0628\u062c\u06a9\u062a\u00a0Number \u0628\u0627 \u0645\u0642\u0627\u062f\u06cc\u0631 \u0639\u062f\u062f\u06cc \u06a9\u0627\u0631 \u0645\u06cc\u200c\u06a9\u0646\u062f.<\/p>\n<h4>Number.<mark>isNaN(<\/mark>x<mark>)<\/mark><\/h4>\n<p>\u0627\u06cc\u0646 \u0645\u062a\u062f \u0645\u0634\u062e\u0635 \u0645\u06cc\u200c\u06a9\u0646\u062f\u060c x \u0645\u0639\u0627\u062f\u0644 NaN \u0627\u0633\u062a \u06cc\u0627 \u0646\u0647.<\/p>\n<pre><code class=\"js\">\r\n\/\/ Numbers\r\n<mark>Number.isNaN(NaN);            \/\/ true <\/mark>\r\nNumber.isNaN(5);              \/\/ false\r\nNumber.isNaN(Infinity);       \/\/ false\r\n\r\n\/\/ Strings\r\nNumber.isNaN(\"5\");            \/\/ false\r\nNumber.isNaN(\"Infinity\");     \/\/ false\r\nNumber.isNaN(\"NaN\");          \/\/ false\r\nNumber.isNaN(\"\");             \/\/ false\r\nNumber.isNaN(\" \");            \/\/ false\r\nNumber.isNaN(\"12n\");          \/\/ false\r\nNumber.isNaN(\"true\");         \/\/ false\r\n\r\n\/\/ Boolean\r\nNumber.isNaN(true);           \/\/ false\r\nNumber.isNaN(false);          \/\/ false\r\n\r\n\/\/ Null\r\nNumber.isNaN(null);           \/\/ false\r\n\r\n\/\/ undefined\r\nNumber.isNaN(undefined);      \/\/ false\r\n\r\n<\/code><\/pre>\n<h4>Number.<mark>isFinite(<\/mark>x<mark>)<\/mark><\/h4>\n<p>\u0627\u06cc\u0646 \u0645\u062a\u062f \u0645\u0634\u062e\u0635 \u0645\u06cc\u200c\u06a9\u0646\u062f\u060c x \u0639\u062f\u062f \u0645\u062d\u062f\u0648\u062f \u0627\u0633\u062a \u06cc\u0627 \u0646\u0647.<\/p>\n<pre><code class=\"js\">\r\n\/\/ Numbers\r\n<mark>Number.isFinite(5);              \/\/ true <\/mark>\r\n<mark>Number.isFinite(0);              \/\/ true <\/mark>\r\n<mark>Number.isFinite(5.2);            \/\/ true <\/mark>\r\n<mark>Number.isFinite(-5.2);           \/\/ true <\/mark>\r\nNumber.isFinite(Infinity);       \/\/ false\r\nNumber.isFinite(NaN);            \/\/ false\r\n\r\n\/\/ Strings\r\nNumber.isFinite(\"5\");            \/\/ false\r\nNumber.isFinite(\"\");             \/\/ false\r\nNumber.isFinite(\" \");            \/\/ false\r\nNumber.isFinite(\"true\");         \/\/ false\r\n\r\n\/\/ Boolean\r\nNumber.isFinite(true);           \/\/ false\r\nNumber.isFinite(false);          \/\/ false\r\n\r\n\/\/ Null\r\nNumber.isFinite(null);           \/\/ false\r\n\r\n\/\/ undefined\r\nNumber.isFinite(undefined);      \/\/ false\r\n\r\n<\/code><\/pre>\n<h4>Number.<mark>isInteger(<\/mark>x<mark>)<\/mark><\/h4>\n<p>\u0627\u06cc\u0646 \u0645\u062a\u062f \u0645\u0634\u062e\u0635 \u0645\u06cc\u200c\u06a9\u0646\u062f\u060c x \u0639\u062f\u062f \u0635\u062d\u06cc\u062d \u0627\u0633\u062a \u06cc\u0627 \u0646\u0647.<\/p>\n<pre><code class=\"js\">\r\n\/\/ Numbers\r\n<mark>Number.isInteger(5);              \/\/ true <\/mark>\r\n<mark>Number.isInteger(0);              \/\/ true <\/mark>\r\n<mark>Number.isInteger(-5);             \/\/ true <\/mark>\r\nNumber.isInteger(5.2);            \/\/ false\r\nNumber.isInteger(Infinity);       \/\/ false\r\nNumber.isInteger(NaN);            \/\/ false\r\n\r\n\/\/ Strings\r\nNumber.isInteger(\"5\");            \/\/ false\r\nNumber.isInteger(\"\");             \/\/ false\r\nNumber.isInteger(\" \");            \/\/ false\r\nNumber.isInteger(\"true\");         \/\/ false\r\n\r\n\/\/ Boolean\r\nNumber.isInteger(true);           \/\/ false\r\nNumber.isInteger(false);          \/\/ false\r\n\r\n\/\/ Null\r\nNumber.isInteger(null);           \/\/ false\r\n\r\n\/\/ undefined\r\nNumber.isInteger(undefined);      \/\/ false\r\n\r\n<\/code><\/pre>\n<hr \/>\n<p><video controls=\"controls\"><source src=\"https:\/\/behnudi.ir\/f\/js1\/05\/js1055.mp4\" type=\"video\/mp4\" \/>Your browser does not support the video tag.<\/video><\/p>\n<hr \/>\n<h4>\u062a\u0645\u0631\u06cc\u0646 \u06f5<\/h4>\n<ul>\n<li>\u0627\u06cc\u0646 <a href=\"https:\/\/behnudi.ir\/f\/js1\/05\/05-5.zip\" download>\u0641\u0627\u06cc\u0644<\/a>\u00a0\u0631\u0627 \u062f\u0627\u0646\u0644\u0648\u062f \u06a9\u0646\u06cc\u062f.<\/li>\n<li>\u0622\u0646 \u0631\u0627 \u062f\u0631 \u0641\u0648\u0644\u062f\u0631 js1 \u0628\u0627\u0632 \u06a9\u0646\u06cc\u062f.<\/li>\n<li>\u062a\u0646\u0647\u0627 \u0641\u0627\u06cc\u0644 script.js \u0631\u0627 \u0645\u06cc\u200c\u062a\u0648\u0627\u0646\u06cc\u062f \u062a\u063a\u06cc\u06cc\u0631 \u062f\u0647\u06cc\u062f.<\/li>\n<li>\u0647\u0631\u06af\u0627\u0647 \u0631\u0648\u06cc \u062f\u06a9\u0645\u0647\u200c\u0647\u0627 \u06a9\u0644\u06cc\u06a9 \u0634\u062f\u060c \u062d\u0627\u0635\u0644 \u0639\u0645\u0644 \u0631\u0648\u06cc \u062e\u0627\u0646\u0647 \u0627\u0648\u0644 \u0631\u0627 \u062f\u0631 \u062e\u0627\u0646\u0647 \u062f\u0648\u0645 \u0628\u0646\u0648\u06cc\u0633\u062f.<\/li>\n<\/ul>\n<p><img decoding=\"async\" class=\"aligncenter size-full wp-image-814\" src=\"https:\/\/behnudi.ir\/f\/js1\/05\/img\/05-5.png\" \/><\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u0627\u0650\u06a9\u0633\u067e\u0631\u0650\u0634\u0646 &#8211; Expression \u062a\u0635\u0648\u06cc\u0631 \u0632\u06cc\u0631 \u0631\u0627 \u0628\u0628\u06cc\u0646\u06cc\u062f \u0648 \u0628\u0627 \u0686\u0646\u062f \u0627\u0635\u0637\u0644\u0627\u062d \u0622\u0634\u0646\u0627 \u0634\u0648\u06cc\u062f. \u0627\u0650\u06a9\u0633\u067e\u0631\u0650\u0634\u0646 (Expression): \u0642\u0637\u0639\u0647\u200c\u0627\u06cc \u0627\u0632 \u06a9\u062f \u06a9\u0647 \u0639\u0645\u0644\u06cc\u0627\u062a\u06cc \u06cc\u0627 \u0645\u062d\u0627\u0633\u0628\u0627\u062a\u06cc \u0631\u0627 \u0627\u0646\u062c\u0627\u0645 \u0645\u06cc \u062f\u0647\u062f \u062a\u0627 \u06cc\u06a9 \u0645\u0642\u062f\u0627\u0631 \u0631\u0627 \u0628\u062f\u0633\u062a \u0622\u0648\u0631\u062f. \u0622\u067e\u0650\u0631\u0650\u06cc\u062a\u0648\u0631 (Operator): \u06cc\u0627 \u0639\u0645\u0644\u06af\u0631 \u0645\u062b\u0644 \u062c\u0645\u0639 \u06cc\u0627 \u0636\u0631\u0628 \u0639\u0645\u0644\u06cc \u0627\u0633\u062a \u06a9\u0647 \u0631\u0648\u06cc \u0645\u0642\u0627\u062f\u06cc\u0631 \u0627\u0646\u062c\u0627\u0645 \u0645\u06cc\u200c\u06af\u06cc\u0631\u062f \u0648 \u0646\u062a\u06cc\u062c\u0647\u200c\u0627\u06cc \u0628\u0647 \u062f\u0633\u062a \u0645\u06cc\u200c\u0622\u06cc\u062f. \u0622\u067e\u0650\u0631\u064e\u0646\u062f (Operand): \u06cc\u0627 [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":1530,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[20],"tags":[46,44],"class_list":["post-1564","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-computer-science","tag-javascript","tag-web-design"],"_links":{"self":[{"href":"https:\/\/behnudi.ir\/index.php?rest_route=\/wp\/v2\/posts\/1564","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/behnudi.ir\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/behnudi.ir\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/behnudi.ir\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/behnudi.ir\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=1564"}],"version-history":[{"count":0,"href":"https:\/\/behnudi.ir\/index.php?rest_route=\/wp\/v2\/posts\/1564\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/behnudi.ir\/index.php?rest_route=\/wp\/v2\/media\/1530"}],"wp:attachment":[{"href":"https:\/\/behnudi.ir\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1564"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/behnudi.ir\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=1564"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/behnudi.ir\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=1564"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}