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Getting Error: DROPDOWN is not a function - Works in IE9

  • 1 respuesta
  • 1 tiene este problema
  • 4 visitas
  • Última respuesta de cor-el

mark.ebling
mark.ebling
more options

I'm trying to remove the default value selected in a drop-down box.

The call to the function is this: onchange="javascript:Remove_Default_Value(this);"

Here is the function: 

function Remove_Default_Value(DROPDOWN) {
 var i = DROPDOWN.options.length - 1;  
 for ( i; i >= 0; i--)   
 {  
  DROPDOWN(i).defaultSelected = false;
 }  
}

The error I'm getting is "DROPDOWN is not a function".

Any ideas is greatly appreciated.

I'm trying to remove the default value selected in a drop-down box. The call to the function is this: onchange="javascript:Remove_Default_Value(this);" Here is the function: <pre><nowiki>function Remove_Default_Value(DROPDOWN) { var i = DROPDOWN.options.length - 1; for ( i; i >= 0; i--) { DROPDOWN(i).defaultSelected = false; } } </nowiki></pre> The error I'm getting is "DROPDOWN is not a function". Any ideas is greatly appreciated.

Modificadas por cor-el el

Solución elegida

It is not a function, but an array and you also need to use getElementsByTagName()

function Remove_Default_Value(DROPDOWN) {
 var i = DROPDOWN.getElementsByTagName("option").length - 1;  
 for ( i; i >= 0; i-- )   
 {  
  DROPDOWN.getElementsByTagName("option")[i].defaultSelected = false;
 }  
}

A good place to ask advice about web development is at the MozillaZine "Web Development/Standards Evangelism" forum.

The helpers at that forum are more knowledgeable about web development issues.
You need to register at the MozillaZine forum site in order to post at that forum.

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cor-el
cor-el
  • Moderator
  • Top 10 Contributor
more options

Solución elegida

It is not a function, but an array and you also need to use getElementsByTagName()

function Remove_Default_Value(DROPDOWN) {
 var i = DROPDOWN.getElementsByTagName("option").length - 1;  
 for ( i; i >= 0; i-- )   
 {  
  DROPDOWN.getElementsByTagName("option")[i].defaultSelected = false;
 }  
}

A good place to ask advice about web development is at the MozillaZine "Web Development/Standards Evangelism" forum.

The helpers at that forum are more knowledgeable about web development issues.
You need to register at the MozillaZine forum site in order to post at that forum.