blocks|key|475100|text|if((Type+==+2+&&+PageCount+==+0)+%7C%7C+(Type+==+2+&&+PageCount+==+''))+{

++++++++PageCount=+document.getElementById('<%25=hfPageCount.ClientID+%25>').value;
}|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|475101|这可能是可能的解决方案之一，因此'or‘是%7C%7C不是!！|unstyled|475102|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$B|C]]|$1|D|3|E|5|F|7|J|8|@]|9|@]|A|$]]|$1|G|3|-4|5|F|7|K|8|@]|9|@]|A|$]]]|H|$]]

<pre><code>if((Type == 2 &amp;&amp; PageCount == 0) || (Type == 2 &amp;&amp; PageCount == '')) {

 PageCount= document.getElementById('&lt;%=hfPageCount.ClientID %&gt;').value;
}
</code></pre>

This could be one of possible solutions, so 'or' is || not !!

blocks|key|475146|text|用一对额外的括号把它们包起来，你就可以开始了。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|475147|if((Type+==+2+&&+PageCount+==+0)+%7C%7C+(Type+==+2+&&+PageCount+==+''))
++++PageCount=+document.getElementById('<%25=hfPageCount.ClientID+%25>').value;
}|code-block|syntax|javascript|475148|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

Wrap them in an extra pair of parens and you're good to go.

<pre><code>if((Type == 2 &amp;&amp; PageCount == 0) || (Type == 2 &amp;&amp; PageCount == ''))
 PageCount= document.getElementById('&lt;%=hfPageCount.ClientID %&gt;').value;
}
</code></pre>

blocks|key|475203|text|整个if应该包括在括号中，并且or运算符是%7C%7C而不是!!，因此|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|475204|if+((Type+==+2+&&+PageCount+==+0)+%7C%7C+(Type+==+2+&&+PageCount+==+''))+{+...|code-block|syntax|javascript|475205|entityMap^0|2|2|F|2|L|2|Q|2|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@$9|N|A|O|B|C]|$9|P|A|Q|B|C]|$9|R|A|S|B|C]|$9|T|A|U|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|V|8|@]|D|@]|E|$I|J]]|$1|K|3|-4|5|6|7|W|8|@]|D|@]|E|$]]]|L|$]]

the whole <code>if</code> should be enclosed in brackets and the <code>or</code> operator is <code>||</code> an not <code>!!</code>, so

<pre><code>if ((Type == 2 &amp;&amp; PageCount == 0) || (Type == 2 &amp;&amp; PageCount == '')) { ...
</code></pre>

blocks|key|691439|text|我目前正在检查大量的条件，如果使用if语句方法超过4个条件，这些条件就会变得很笨拙。只是为了给未来的观众分享一个看起来干净的替代品。它的伸缩性很好，我使用：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|691440|var+a+=+0;
var+b+=+0;

a+%2B=+("condition+1")?+1+:+0;+b+%2B=+1;
a+%2B=+("condition+2")?+1+:+0;+b+%2B=+1;
a+%2B=+("condition+3")?+1+:+0;+b+%2B=+1;
a+%2B=+("condition+4")?+1+:+0;+b+%2B=+1;
a+%2B=+("condition+5")?+1+:+0;+b+%2B=+1;
a+%2B=+("condition+6")?+1+:+0;+b+%2B=+1;
//+etc+etc

if(a+==+b)+{
++++//do+stuff
}|code-block|syntax|javascript|691441|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

I am currently checking a large number of conditions, which becomes unwieldy using the if statement method beyond say 4 conditions. Just to share a clean looking alternative for future viewers... which scales nicely, I use: 

<pre><code>var a = 0;
var b = 0;

a += ("condition 1")? 1 : 0; b += 1;
a += ("condition 2")? 1 : 0; b += 1;
a += ("condition 3")? 1 : 0; b += 1;
a += ("condition 4")? 1 : 0; b += 1;
a += ("condition 5")? 1 : 0; b += 1;
a += ("condition 6")? 1 : 0; b += 1;
// etc etc

if(a == b) {
 //do stuff
}
</code></pre>

blocks|key|691494|text|有时，您可以找到进一步组合语句的技巧。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|691495|例如：|691496|0+%2B+0+=+0|code-block|syntax|javascript|691497|和|691498|""+%2B+0+=+0|691499|所以|691500|PageCount+==+0
PageCount+==+''|691501|可以这样写：|691502|PageCount%2B0+==+0|691503|在javascript中，0和false+inverting+!一样好，它可以将0转换为true|offset|length|style|CODE|691504|!PageCount%2B0|691505|总计为：|691506|if+(+Type+==+2+&&+!PageCount%2B0+)+PageCount+=+elm.value;|691507|entityMap^0|0|0|0|0|0|0|0|0|0|D|1|F|5|V|1|14|1|18|4|0|0|0|0^^$0|@$1|2|3|4|5|6|7|18|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|19|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|1A|8|@]|9|@]|A|$G|H]]|$1|I|3|J|5|6|7|1B|8|@]|9|@]|A|$]]|$1|K|3|L|5|F|7|1C|8|@]|9|@]|A|$G|H]]|$1|M|3|N|5|6|7|1D|8|@]|9|@]|A|$]]|$1|O|3|P|5|F|7|1E|8|@]|9|@]|A|$G|H]]|$1|Q|3|R|5|6|7|1F|8|@]|9|@]|A|$]]|$1|S|3|T|5|F|7|1G|8|@]|9|@]|A|$G|H]]|$1|U|3|V|5|6|7|1H|8|@$W|1I|X|1J|Y|Z]|$W|1K|X|1L|Y|Z]|$W|1M|X|1N|Y|Z]|$W|1O|X|1P|Y|Z]|$W|1Q|X|1R|Y|Z]]|9|@]|A|$]]|$1|10|3|11|5|F|7|1S|8|@]|9|@]|A|$G|H]]|$1|12|3|13|5|6|7|1T|8|@]|9|@]|A|$]]|$1|14|3|15|5|F|7|1U|8|@]|9|@]|A|$G|H]]|$1|16|3|-4|5|6|7|1V|8|@]|9|@]|A|$]]]|17|$]]

Sometimes you can find tricks to further combine statments.

Like for example:

<pre><code>0 + 0 = 0
</code></pre>

and

<pre><code>"" + 0 = 0
</code></pre>

so

<pre><code>PageCount == 0
PageCount == ''
</code></pre>

can be written like:

<pre><code>PageCount+0 == 0
</code></pre>

In javascript <code>0</code> is just as good as <code>false</code> inverting <code>!</code> it would turn <code>0</code> into <code>true</code>

<pre><code>!PageCount+0
</code></pre>

for a grand total of:

<pre><code>if ( Type == 2 &amp;&amp; !PageCount+0 ) PageCount = elm.value;
</code></pre>

blocks|key|691552|text|这里有一种替代方法。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|691553|const+conditionsArray+=+[
++++condition1,+
++++condition2,
++++condition3,
]

if+(conditionsArray.indexOf(false)+===+-1)+{
++++"do+somthing"
}|code-block|syntax|javascript|691554|或ES7%2B|691555|if+(!conditionsArray.includes(false))+{
+++"do+somthing"
}|691556|entityMap^0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|N|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|O|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|K|3|-4|5|6|7|Q|8|@]|9|@]|A|$]]]|L|$]]

Here is an alternative way to do that.
<pre><code>const conditionsArray = [
 condition1, 
 condition2,
 condition3,
]

if (conditionsArray.indexOf(false) === -1) {
 &quot;do somthing&quot;
}
</code></pre>
Or ES7+
<pre><code>if (!conditionsArray.includes(false)) {
 &quot;do somthing&quot;
}
</code></pre>

blocks|key|691560|text|function+go(type,+pageCount)+{
++++if+((type+==+2+&&+pageCount+==+0)+%7C%7C+(type+==+2+&&+pageCount+==+''))+{
++++++++pageCount+=+document.getElementById('<%25=hfPageCount.ClientID+%25>').value;
++++}
}|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|691561|unstyled|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|G|8|@]|9|@]|A|$B|C]]|$1|D|3|-4|5|E|7|H|8|@]|9|@]|A|$]]]|F|$]]

<pre class="lang-js prettyprint-override"><code>function go(type, pageCount) {
 if ((type == 2 &amp;&amp; pageCount == 0) || (type == 2 &amp;&amp; pageCount == '')) {
 pageCount = document.getElementById('&lt;%=hfPageCount.ClientID %&gt;').value;
 }
}
</code></pre>

blocks|key|475473|text|OR运算符|type|unstyled|depth|inlineStyleRanges|entityRanges|data|475474|if+(+con1+==+True+%7C%7C+con2+==+True+%7C%7C+con3+==+True){
+++++//+statement+...
}|code-block|syntax|javascript|475475|AND运算符|475476|if+(+con1+==+True+&&+con2+==+True+&&+con3+==+True){
+++++//+statement+...
}|475477|适用于我的:D|475478|entityMap^0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|O|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|Q|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|R|8|@]|9|@]|A|$E|F]]|$1|K|3|L|5|6|7|S|8|@]|9|@]|A|$]]|$1|M|3|-4|5|6|7|T|8|@]|9|@]|A|$]]]|N|$]]

OR Operator
<pre><code>if ( con1 == True || con2 == True || con3 == True){
 // statement ...
}
</code></pre>
AND Operator
<pre><code>if ( con1 == True &amp;&amp; con2 == True &amp;&amp; con3 == True){
 // statement ...
}
</code></pre>
Works on mine :D

Here is how I mention two conditions if this or this 

<pre><code>if (Type == 2 &amp;&amp; PageCount == 0) || (Type == 2 &amp;&amp; PageCount == '')
 PageCount= document.getElementById('&lt;%=hfPageCount.ClientID %&gt;').value;
}
</code></pre>

How to specify multiple conditions in an if statement in javascript

下面是我如何提到这两种情况的方法if (Type == 2 && PageCount == 0) || (Type == 2 && PageCount == '') PageCount= document.getElementById('<%=hfPageCount.ClientID %>').value;}

问如何在javascript中的if语句中指定多个条件
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