Let's press the button
This time, the number doesn't increase.
Each time you press the onclick button,
in the alert(i) popup window shown to the user, the variable i, which represents the number,
is a local variable that runs only inside the function called "one_plus()".
Why??? The reason is simple. !!!
Because it was written inside the function, (if you put a sink in the living room, you can also use it in the living room.)
i+=1; runs only within the function.
So then?
Is there no way to write it inside the function and still use it outside?
To answer first,
"Yes, there is."
It's simple. When declaring the variable,
in front of it,
just drop the "var" and declare it.
Now let's stop thinking and talking, and just try it.
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<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="ko" lang="ko"> |
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<head> |
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<meta http-equiv="Content-Type" content="application/xhtml+xml; charset=UTF-8" /> |
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<title> 사용자 정의 함수3.지역변수 </title> |
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<script type="text/javascript"> |
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//<!CDATA[ |
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function one_plus(){ |
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var i=0; //지역변수 |
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i+=1; |
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alert(i); |
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} |
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// onclick -> 클릭할 때 마다 1씩증가 X |
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//]]]]]]> |
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</script> |
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</head> |
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<body> |
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<form method="post" action""]]> |
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<p> |
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<input type="button" value="one plus one" onclick="one_plus()" /> |
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</p> |
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</form> |
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</body> |
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</html> |
