用Javascript实现ListBox的增或者是删[1]

javascript对ListBox的增或者是删

假设有个ListBoxID分别为lbLeftlbRight

选中lbLeft里的项添加到lbRight里:

function add()

{

var left;

var right;

left = documentgetElementById(lbLeft);

right = documentgetElementById(lbRight);

for(var i=;i<leftlength;i++)

{

if(leftoptions[i]selected)

{

//判断该项是否已经存在

for(j=;j<rightlength;j++)

{

if(rightoptions[j]value==leftoptions[i]value)

{

return;

}

}

rightadd(new Option(leftoptions[i]textleftoptions[i]value));

}

}

}

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