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[数组]请问错出在哪里了

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Release: 2016-06-23 13:37:25
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<?php$rc = array("07-12"=>"同学聚会", "07-21"=>"信用还贷", "07-23"=>"购买商品");$date = "07-23";foreach($rc as $key=>$value){if($key == $date){echo "<script>alert('".$key."日备忘:".$value."')</script>";break;}else{echo "<script>alert('无备忘')</script>";break;}}?>
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第三行如果是:$date = "07-12", 弹出提示框:07-12日备忘:同学聚会
第三行如果是:$date = "07-21",或者是: $date = "07-23",应该同上类似,但是弹出提示框:无备忘
请问错出在哪里了?


回复讨论(解决方案)

你不是有break吗,遍历一次就退出了。

同楼上,第10行不能break

$rc = array("07-12"=>"同学聚会", "07-21"=>"信用还贷", "07-23"=>"购买商品");$date = "07-23";$msg = '';foreach($rc as $key=>$value){  if($key == $date){    $msg = "<script>alert('".$key."日备忘:".$value."')</script>";    break;  }}if(! $msg) $msg = "<script>alert('无备忘')</script>";echo $msg;
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想想为什么

$rc = array("07-12"=>"同学聚会", "07-21"=>"信用还贷", "07-23"=>"购买商品");$date = "07-23";$msg = '';foreach($rc as $key=>$value){  if($key == $date){    $msg = "<script>alert('".$key."日备忘:".$value."')</script>";    break;  }}if(! $msg) $msg = "<script>alert('无备忘')</script>";echo $msg;
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想想为什么

正解。谢谢楼上诸位。

可是为什么这样写,我还没想明白。

这样写明白吗?

$rc = array("07-12"=>"同学聚会", "07-21"=>"信用还贷", "07-23"=>"购买商品");$date = "07-23";$msg = "<script>alert('无备忘')</script>";//给个初值foreach($rc as $key=>$value){  if($key == $date){ //如果存在就修改    $msg = "<script>alert('".$key."日备忘:".$value."')</script>";    break;//只是为了提前结束循环  }}echo $msg;
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xuzuning兄游刃有余,6楼的代码通俗易懂。
我用netbeans-xdebug运行了1楼的代码,单步查看变量值的变化,明白1楼代码的错误所在了。
1楼代码如果第三行是:$date = "07-21"; 第一次循环时,$key为07-12,不等于$date07-21,这时弹出js提示框是"无备忘", 而不是希望弹出的:“07-21日备忘:信用还贷”。
正确的方法应该是这时不弹出提示框,而是到$key==$date时才弹出提示框。
这种情况下一个循环里不能有两套echo。

很基础的问题,不注意的确会绕进去!

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