Ext.form.TextField 浏览框监听事件无法执行，求高手解答

Question

var cust_person_file_upload_photoName = new Ext.form.TextField({
name:'photoName',
inputType:'file',
fieldLabel:'上传证件',
id:'src_photoName',
width: 120,
change: function(field, newValue, oldValue){
alert(0);
var img_reg = /\.([jJ][pP][gG]){1}$|\.([jJ][pP][eE][gG]){1}$|\.([gG][iI][fF]){1}$|\.([pP][nN][gG]){1}$|\.([bB][mM][pP]){1}$/
        var url = 'file:///' + Ext.get('src_photoName').dom.value;
        Ext.MessageBox.alert("kkk",Ext.get('src_photoName').dom);
        if (img_reg.test(url)) {
            if (Ext.isIE7) {
                var image = Ext.get('file_imageBrowse').dom;
                image.src = Ext.BLANK_IMAGE_URL;// 覆盖原来的图片
                image.filters
                        .item("DXImageTransform.Microsoft.AlphaImageLoader").src = url;
            } else {
                Ext.get('file_imageBrowse').dom.src = getFullPath(Ext.get('src_photoName').dom);
            }
        }
    }
});

Answer 1

listeners : {
             change: function(field, newValue, oldValue){
                  alert(0);
                }
     }

Answer 2

Ext.onReady(function()
{ var cust_person_file_upload_photoName = new Ext.form.TextField({
name : 'photoName',
inputType : 'file',
renderTo : Ext.getBody(),
fieldLabel : '上传证件',
id : 'src_photoName',
width : 120,
listeners : {
'change' : function(field, newValue, oldValue)
{
alert(0);
var img_reg = /\.([jJ][pP][gG]){1}$|\.([jJ][pP][eE][gG]){1}$|\.([gG][iI][fF]){1}$|\.([pP][nN][gG]){1}$|\.([bB][mM][pP]){1}$/
var url = 'file:///' + Ext.get('src_photoName').dom.value;
Ext.MessageBox.alert("kkk", Ext.get('src_photoName').dom);
if (img_reg.test(url))
{
if (Ext.isIE7)
{
var image = Ext.get('file_imageBrowse').dom;
image.src = Ext.BLANK_IMAGE_URL;// 覆盖原来的图片
image.filters
.item("DXImageTransform.Microsoft.AlphaImageLoader").src = url;
}
else
{
Ext.get('file_imageBrowse').dom.src = getFullPath(Ext
.get('src_photoName').dom);
}
}
}
} });
})