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

  • 1 回覆
  • 1 有這個問題
  • 4 次檢視
  • 最近回覆由 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.

由 cor-el 於 修改

被選擇的解決方法

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.

從原來的回覆中察看解決方案 👍 0

所有回覆 (1)

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

選擇的解決方法

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.