Reference variable dynamically?

[eseabrook2008]

Basically, I'm in a For loop and I need to assign a value to a variable depending on the value of the counter. Variable names are: glbnumconvict1, glbnumconvict2, glbnumconvict3, and glbnumconvict4. I opted to declare the variables before hand so they exist when I try to assign the value but how do I do the assignment:

for (x=1, x<5, x++) {
if (getField("txtsomefield"+x).value == "") {
"glbnumconvict"+x = somepassednumber}}

Does this make sense? If I try the above, i get an invalid left-hand assignment on the glbnumconvict line.

 

[feherke]

Hi

That is why arrays were invented...

var glbnumconvict=[0,0,0,0,0]
for (x=1, x<5, x++) {
  if (getField("txtsomefield"+x).value == "") {
    glbnumconvict[x] = somepassednumber
  }
}

Feherke.

http://rootshell.be/~feherke/

 

[eseabrook2008]

Oh man...I was making this much harder than it was! Thanks!

 

[feherke]

Hi

Note that array element numbering in JavaScript starts from 0. Keeping that in mind and numbering related document elements accordingly could help.

[gray]// fields : txtsomefield1 .. txtsomefield4[/gray]
[gray]// array : 5 elements ( 0 is just placeholder, 1-4 used )[/gray]
var glbnumconvict=[[red]0,[/red]0,0,0,0]
for (x=[red]1[/red], x<[red]5[/red], x++) {
  if (getField("txtsomefield"+x).value == "") {
    glbnumconvict[x] = somepassednumber
  }
}

[gray]// fields : txtsomefield1 .. txtsomefield4[/gray]
[gray]// array : 4 elements ( all used )[/gray]
var glbnumconvict=[0,0,0,0]
for (x=[red]0[/red], x<[red]4[/red], x++) {
  if (getField("txtsomefield"+[red]([/red]x[red]+1)[/red]).value == "") {
    glbnumconvict[x] = somepassednumber
  }
}

[gray]// fields : txtsomefield0 .. txtsomefield3[/gray]
[gray]// array : 4 elements ( all used )[/gray]
var glbnumconvict=[0,0,0,0]
for (x=[red]0[/red], x<[red]4[/red], x++) {
  if (getField("txtsomefield"+x).value == "") {
    glbnumconvict[x] = somepassednumber
  }
}

Feherke.

http://rootshell.be/~feherke/

 

[tsuji]

Just to answer the question as it was.
>"glbnumconvict"+x = somepassednumber
If glbnumconvict1 etc are global (as glb might suggest), it is this.
[tt] window["glbnumconvict"+x] = somepassednumber[/tt]
If glbnumconvict1 etc are actually local to the function, it is this.
[tt] eval("glbnumconvict"+x+"=samepassednumber");[/tt]
If you find other way of structuring variables (such as array), I have no objection, as long as you're happy.

 

[shadedecho]

an easier way (IMHO) than even an array, which preserves the name'ness of your variables when using them later (instead of having to remember array 0-indexing and do stuff like myvar[0]), is to set dynamic properties on an object, like this:

var glbnumconvict = {}; // declare empty object

for (var x=1; x<5; x++) {
  if (getField("txtsomefield"+x).value == "") {
    glbnumconvict["v"+x] = somepassednumber;
  }
}
alert(glbnumconvict.v3); // print the value of the third variable

Notice how that alert() statement using one of your variables has a nicer looking (an easier to remember) syntax than the [ ] 0-indexing array syntax.