Uncaught reference error:False is not defined

Question

I have the following call to javascript:

protected override void OnPreRender(EventArgs e)
    {
        base.OnPreRender(e);

        this._BtAdd.Attributes.Add("onclick", "GXDualListBox_MoveDualList(" + sourceListId + ",  " + destListId + ",  " + selectedValuesId + ", false, true, "+ this._SortByDescription +");");
        this._BtRemove.Attributes.Add("onclick", "GXDualListBox_MoveDualList(" + destListId + ",  " + sourceListId + ",  " + selectedValuesId + ", false, false, " + this._SortByDescription + ");");

        if (!this._PostBackOnAll)
        {
            this._BtAddAll.Attributes.Add("onclick", "GXDualListBox_MoveDualList(" + sourceListId + ",  " + destListId + ",  " + selectedValuesId + ", true, true, " + this._SortByDescription + " );");
            this._BtRemoveAll.Attributes.Add("onclick", "GXDualListBox_MoveDualList(" + destListId + ",  " + sourceListId + ",  " + selectedValuesId + ", true, false, " + this._SortByDescription + " );");
        }

        // Check if user can double-click on listbox item to move it
        if (this._AllowDblClick)
        {
            this._LstSource.Attributes.Add("ondblclick", "GXDualListBox_MoveDualList(" + sourceListId + ",  " + destListId + ",  " + selectedValuesId + ", false, true, " + this._SortByDescription + " );");
            this._LstDestination.Attributes.Add("ondblclick", "GXDualListBox_MoveDualList(" + destListId + ",  " + sourceListId + ",  " + selectedValuesId + ", false, false, " + this._SortByDescription + " );");
        }
    }

this._SortByDescription is bool which would be false in this case. The javascript is as follows:

function GXDualListBox_MoveDualList(srcList, destList, selectedValues, moveAll, isAdd,sortByDescription) 
{

if ((srcList.selectedIndex == -1) && (moveAll == false)) {
    return;
}
newDestList = new Array(destList.options.length);

for (var len = 0; len < destList.options.length; len++) {
    if (destList.options[len] != null) {
        newDestList[len] = new Option(destList.options[len].text, destList.options[len].value, destList.options[len].defaultSelected, destList.options[len].selected);
    }
}
for (var i = 0; i < srcList.options.length; i++) {
    if (srcList.options[i] != null && (srcList.options[i].selected == true || moveAll)) {
            newDestList[len] = new Option(srcList.options[i].text, srcList.options[i].value, srcList.options[i].defaultSelected, srcList.options[i].selected);
            len++;
    }
}

if (sortByDescription) {
    newDestList.sort(GXDualListManager_CompareOptionValues);   
    newDestList.sort(GXDualListManager_CompareOptionText);  
}


for (var j = 0; j < newDestList.length; j++) {
    if (newDestList[j] != null) {
        destList.options[j] = newDestList[j];
    }
}   
}

if (isAdd)
    buildSelectedList(destList, selectedValues);
else
    buildSelectedList(srcList, selectedValues);
} 

When I hard code this._SortByDescription as 'false' in the javascript call, it works. But replacing 'false' with this._SortByDescription results in error. Also I observed while debugging that the javascript receives the value of this._SortByDescription as 'False' instead of 'false'. Not sure if this matters. I am working on javascript for the first time. Please help.

Answer 1

Try converting to lower case:

this._SortByDescription.ToLower();

If the property of type bool:

this._SortByDescription.ToString().ToLower();

Answer 2

You could also define "True" and "False" in the beginning of your function/JS. It may seem tedious, but it worked for me.

function xxx {
    var True = true;
    var False = false;

    // code...
}