无法输出简单数组？ [英] Can't output simple array?

问题描述

我一直在试图弄清为什么我的数组不输出。

我在数组上做了一个var dump，它可以很好地转储，但是当我尝试输出它，它返回致命错误。另外，我发现也许我可能必须遍历数组才能访问它，所以我也尝试了一下，并通过执行var dump设法遍历了数组，但是当我输出它时，它破坏了页面。 / p>

这是我尝试过尝试将近3个小时的代码，尝试各种事情。

ColdFusion：

 < cfset defaultDirectory = C：\uploads\ /> 
 
< cfdirectory 
 directory =＃defaultDirectory＃ 
 action = list 
 name = myList 
> 
 
<！---获取目录名称数组---> 
< cfquery dbtype = query name = fileNames> 
从myList 
中选择名称
< / cfquery> 
 
<！-创建数组---> 
< cfset myArray = arraynew（1）> 
 
<！---使用目录查询数据名称填充数组---> 
< cfloop query = fileNames> 
< cfset myArray [CurrentRow] [1] =＃defaultDirectory＃&姓名&  \> 
< / cfloop 
  

到目前为止，一切似乎都进展顺利。我转储了数组变量，并输出了我想要的。因此，我尝试了此操作，并返回了致命错误。

 < cfoutput> 
 
< cfif directoryExists（＃myArray [1]＃）> 
它存在。 
< cfelse> 
不存在。 
< / cfif> 
 
< cfoutput> 
  

这是要转储的变量的屏幕截图。

然后我想也许是我必须遍历数组才能访问它？

所以我尝试了这个。

 < cfloop index = i从= 1到=＃arrayLen（myArray）＃> 
< cfdump var =＃myArray [i]＃ 
< / cfloop> 
  

这设法转储了数组中的所有内容，但是当我尝试输出时，它返回一个致命错误我不确定为什么。我查阅了有关如何转储阵列的教程，但不确定自己做错了什么吗？任何建议，将不胜感激。

以下是请求的myArray结构的屏幕截图：

我做了

 < cfvar dump =＃myArray＃> 
  

解决方案

您有一系列结构。因此，您不能简单地将数组值输出为字符串。

您需要引用数组索引以及结构的键以提取值。

像这样的伪代码： arrayName [arrayIndex] [structureKey] 。看起来您可以在初始代码示例中使用它。此处：

 < cfset myArray [CurrentRow] [1] =＃defaultDirectory＃&姓名&  \> 
  

这让我感到困惑，因为您的结构键恰好是数字 1 。因此，它看起来像是索引或类似内容。

我创建了一个要点，向您展示了一个有效的示例-

因此您的代码应如下所示：

 < cfif directoryExists（＃myArray [1] [1]＃）> 
它存在。 
< cfelse> 
不存在。 
< / cfif> 
  

或者如果将其包装成这样的循环：

 < cfloop index = i从= 1到=＃arrayLen（myArray）＃> 
< cfif directoryExists（＃myArray [i] [1]＃）> 
它存在。 
< cfelse> 
不存在。 
< / cfif> 
< / cfloop> 
  

I've been trying to figure out why my array won't output.

I did a var dump on the array and it dumps it just fine but when I try to output it, it returns fatal error. In addition, I figured that maybe I had to probably loop over the array in order to access it, so I tried that too and managed to loop over the array by doing a var dump but when I output it, it breaks the page.

Here is my code that I attempted i've been trying for almost 3 hours now trying various things.

ColdFusion:

<cfset defaultDirectory = "C:\uploads\" />

<cfdirectory
   directory="#defaultDirectory#"
   action="list"
   name="myList"
>

<!---Get Array of Directory Names --->
<cfquery dbtype="query" name="fileNames">
    SELECT NAME
    FROM myList
</cfquery>

<!---Create array --->
<cfset myArray=arraynew(1)>

<!---Populate array with directory query data "name" --->
<cfloop query="fileNames">
    <cfset myArray[CurrentRow][1]=#defaultDirectory# & NAME & "\">
</cfloop

Up to this point, everything seemed to be going good. I dumped out the array variable and it outputted what I wanted. So I tried this and it returned a fatal error.

<cfoutput>

<cfif directoryExists("#myArray[1]#")>
   it exists.
   <cfelse>
   Doesn't exists.
</cfif>

<cfoutput>

Here is the screenshot of the variable being dumped.

What I then figured was maybe I have to loop over the array in order to access it?

so I tried this.

<cfloop index="i" from="1" to="#arrayLen(myArray)#">
   <cfdump var="#myArray[i]#"
</cfloop>

this managed to dump out all things from the array but when i try to output it, it returns a fatal error I'm not sure why. I looked up tutorials on how to dump the array and I'm not sure what I'm doing wrong? Any suggestions would be appreciated.

Here is a screenshot of the structure of myArray that was requested:

I did

<cfvar dump="#myArray#">

解决方案

You have an array of structures. So you cannot simply output the array value as a string; that is why you are getting an error.

You need to reference the array index as well as the structure's key to extract the value. Something like this pseudo-code: arrayName[arrayIndex][structureKey]. It looks like you have it working in the initial code example. Here:

<cfset myArray[CurrentRow][1]=#defaultDirectory# & NAME & "\">

It was confusing to me because your structure key happens to be the number 1. So it looked like an index or something.

I created a gist to show you a working example - TryCF Gist. Here is the code I wrote:

<cfscript>
structA = {1="C:\uploads\101 San Fernando"};
structB = {1="C:\uploads\121 Tasman"};
structC = {1="C:\uploads\360 Residences"};
structD = {1="C:\uploads\481 On Mathilda"};

myArray = [];
ArrayAppend(myArray,structA);
ArrayAppend(myArray,structB);
ArrayAppend(myArray,structC);
ArrayAppend(myArray,structD);

writeDump(myArray);

//writeOutput(myArray[1][1]);

for (i=1;i LTE ArrayLen(myArray);i=i+1) {
  writeOutput('<p>' & myArray[i][1] & '</p>');
}
</cfscript>

The output for that code is:

So your code should look like this:

<cfif directoryExists("#myArray[1][1]#")>
   it exists.
<cfelse>
   Doesn't exists.
</cfif>

Or if you wrap that in a loop like this:

<cfloop index="i" from="1" to="#arrayLen(myArray)#">
    <cfif directoryExists("#myArray[i][1]#")>
       it exists.
    <cfelse>
       Doesn't exists.
    </cfif>
</cfloop>

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