代码片段：

var role=s[0].Role;// role contains string value 
dijit.byId("editRole").attr("Value",getRoleByName(role));

function getRoleByName(role)
{
    var roleVal;
    alert(role);
    switch(role)
    {
        case 'Basic User' :roleVal='1';break;
        case 'Network Operator' :roleVal='3';break;
        case 'System Administrator' :roleVal='5';break;
        case 'Custom Level 1' :roleVal='11';break;
        case 'Custom Level 2' : roleVal='12';break;
        default: roleVal='1';break;
    }
    return roleVal;
}

当我试图调用Javascript方法，其中有开关语句，我得到下面的错误在IE8中，但在Firefox中工作正常。
开发人员工具中的错误：

method Error executing: function(/*Event*/ e){
    // summary:
    // Handler when the user activates the button portion.
    if(this._onClick(e) === false){ // returning nothing is same as true
        e.preventDefault(); // needed for checkbox
    } else if (this.type == "submit" && !this.focusNode.form){ // see if a nonform widget needs to be signalled
        for(var node=this.domNode; node.parentNode/*#5935*/; node=node.parentNode){
            var widget=dijit.byNode(node);
            if(widget && typeof widget._onSubmit == "function"){
                widget._onSubmit(e);
                break;
            }
        }
    }
}TypeError: Object doesn't support this property or method

有人能帮我吗？...如何克服这个问题？...