?

例子

<script>var a = "heh"function findLove(){console.log(a);function findforyou(){var a ="you";console.log(a);}function findother(){console.log(a)}findforyou();findother();}findLove(); </script>

輸出

heh you heh

?

例子

<script>var test_id = "my love";if(true){console.log(test_id);var test_id = "where my love?";console.log(test_id);}console.log(test_id); </script>

輸出

my love where my love? where my love?

?

例子

<script>var test_id = "my love";function findLove(){var test_id ;console.log(test_id);test_id = "is you?";console.log(test_id);}findLove();console.log(test_id); </script>

輸出

undefined is you? my love

?

例子

<script>var a = "heh"if(true){console.log(a);} </script>

輸出

heh

?

例子

<script>var a = "heh"function findLove(){console.log(a);}findLove(); </script>

輸出

heh

?

例子

<script>var a = "heh"function findLove(){console.log(a);var a}findLove(); </script>

輸出

undefined

?

轉載于:https://www.cnblogs.com/sea-stream/p/10755335.html

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