blocks|key|2374239|text|使用==与使用if(something)不同，此测试将给出您预期的结果：|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|2374240|function+truthyFalsyTest()
{
++++if(0)+
++++{
+++++++console.log("true");
++++}
++++else
++++{
++++++++console.log("false");
++++}

++++if(1)+
++++{
+++++++console.log("true");
++++}
++++else
++++{
++++++++console.log("false");
++++}

++++if(2)+
++++{
+++++++console.log("true");
++++}
++++else
++++{
++++++++console.log("false");
++++}

++++if(2222)+
++++{
+++++++console.log("true");
++++}
++++else
++++{
++++++++console.log("false");
++++}
}

truthyFalsyTest();|code-block|syntax|javascript|2374241|entityMap^0|2|2|7|D|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@$9|N|A|O|B|C]|$9|P|A|Q|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|R|8|@]|D|@]|E|$I|J]]|$1|K|3|-4|5|6|7|S|8|@]|D|@]|E|$]]]|L|$]]

using <code>==</code> is different from <code>if(something)</code>
This test will give you your expected results:

<pre><code>function truthyFalsyTest()
{
 if(0) 
 {
 console.log("true");
 }
 else
 {
 console.log("false");
 }

 if(1) 
 {
 console.log("true");
 }
 else
 {
 console.log("false");
 }

 if(2) 
 {
 console.log("true");
 }
 else
 {
 console.log("false");
 }

 if(2222) 
 {
 console.log("true");
 }
 else
 {
 console.log("false");
 }
}

truthyFalsyTest();
</code></pre>

blocks|key|2585364|text|In+JavaScript+(==)是一个执行类型转换的相等运算符运算符。更严格的(===)标识运算符不会进行类型转换。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|2585365|例如，即使数字不是布尔值，如果使用(==)运算符，也可以在需要布尔值的地方使用数值。|2585366|但是，如果您强制使用更严格的(+===+)运算符，您将看到'1+===+true‘的计算结果为false。|2585367|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|H|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|I|8|@]|9|@]|A|$]]|$1|D|3|E|5|6|7|J|8|@]|9|@]|A|$]]|$1|F|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|G|$]]

In JavaScript (==) is an equality operator operator where type conversion is done. The more strict (===) identity operator will not do type conversion.

For example, even though a number is not a boolean, you can use a numeric value where a boolean value is expected if using the (==) operator.

But, if you enforce the stricter (===) operator, you will see that '1 === true' will evaluate to false.

blocks|key|2374276|text|0为假，这并不意味着其他数字将为真。简单的例子。如果您在条件中使用===，那么您将看到所有数字的false。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|2374277|(0+==+true)+//+false
(1+==+true)+//+true|code-block|syntax|javascript|2374278|它工作得很好。但是，在下面的示例中，我没有使用not运算符(!)在这种情况下。因此，如果条件为true，则应输出true，否则输出false。尽管如此，它还是会给你带来相反的结果。|2374279|if(0){console.log("true")}else{console.log("false")}+//+false
if(1){console.log("true")}else{console.log("false")}+//+true
if(15){console.log("true")}else{console.log("false")}+//+true|2374280|现在，如果你将数字转换成布尔值，那么它会给出你所想的结果。|2374281|Boolean(0)+==+true+//+false
Boolean(1)+==+true+//+true
Boolean(2)+==+true+//+true
Boolean(othernumber)+==+true+//+true|2374282|谢谢|2374283|entityMap^0|0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|S|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|T|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|U|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|V|8|@]|9|@]|A|$E|F]]|$1|K|3|L|5|6|7|W|8|@]|9|@]|A|$]]|$1|M|3|N|5|D|7|X|8|@]|9|@]|A|$E|F]]|$1|O|3|P|5|6|7|Y|8|@]|9|@]|A|$]]|$1|Q|3|-4|5|6|7|Z|8|@]|9|@]|A|$]]]|R|$]]

0 is false that doesn't mean othernumber will be true.. 
Simple example. If you use === in condition then you will see the false for all numbers.

<pre><code>(0 == true) // false
(1 == true) // true
</code></pre>

It works fine. However, in below example, I have not used not operator (!) in the condition. So if condition is true it should print true else false.
Still it will give you reverse result.

<pre><code>if(0){console.log("true")}else{console.log("false")} // false
if(1){console.log("true")}else{console.log("false")} // true
if(15){console.log("true")}else{console.log("false")} // true
</code></pre>

Now if you convert numbers to Boolean then it will give the result what you were thinking.

<pre><code>Boolean(0) == true // false
Boolean(1) == true // true
Boolean(2) == true // true
Boolean(othernumber) == true // true
</code></pre>

Thanks

Based on these rules:

Falsy:

<ul>
<li>false</li>
<li>0 (zero)</li>
<li>'' or "" (empty string)</li>
<li>null</li>
<li>undefinded</li>
<li>NaN (e.g. the result of 1/0)</li>
</ul>

Truthy: Everything else

I fail to find the correct explanation as to why in following tests, only number 1 evaluates to "true"

<pre><code>0 == true ("false")
1 == true ("true")
2 == true ("false")
othernumber == true ("false")
</code></pre>

javascript truthy numbers

基于这些规则：Falsy:false0 (零)空string)nullundefindedNaN‘’or "“((例如1/0的结果)真理： Everything我找不到正确的解释，为什么在下面的测试中，只有数字1评估为"true“0 == true ("false")1 == true ("true")2 == tru...

问javascript真实数字
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