Strings to Arrays and Back
This applet demonstrates how array data may be stored to
and recovered from strings. For example:
- Type 'f' and tap [Add to Array];
- Type 'a' and tap [Add to Array];
- Tap on the top text entry field to change focus;
- Add in ':c:d:g:e:b';
- Tap [Sort Array].
Discussion
Tapping on [Add to Array] directly adds data to the array data
structure. This structure is converted to a string and shown
in the text box labeled "String". This field, too, may
be edited. When it senses a field "blur" event, it transforms
its string into an array. This array can be sorted, transformed
back to a string, and displayed.
This method of converting arrays to strings and back will be
particularly useful to PERL programmers.
// String to Array
function stringArray(aString)
{
var i = 0
var idx = 0
var s = ""+aString
if (s == "")
{
// this.length = 0
return this
}
// search for the colon to create each array item
while ((idx = s.indexOf(':')) != -1)
{
this[i] = s.substring(0, idx)
s = s.substring(idx+1,s.length)
i++
}
// create final array item
this[i]=s
// this.length = i+1
return this
}
// Array to String
function arrayString(anArray, len)
{
var s = ""
for (var i = 0; i < (len - 1); i++) s += anArray[i]+":"
if (len > 0) s += anArray[len - 1]
return s
}
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