if(navigator.appName.indexOf("Explorer") > -1){//ie
    var exp = 1;
}else{//for ff
    var exp = 2;
}

function buildGlobalDiv(zIndex,nohide){
        var globalDiv = document.createElement( 'div' );
        globalDiv.id = 'globalDiv';
        
        if( 1 == exp ){
            globalDiv.style.filter = 'alpha(opacity=30)';
            globalDiv.style.zIndex = zIndex; 
            
        }else{
            globalDiv.style.opacity = 30/100;
        }
        document.getElementsByTagName('body').item(0).appendChild( globalDiv );
        globalDiv.style.position = 'absolute';
        globalDiv.style.top=0;
        globalDiv.style.left=0; 
        globalDiv.style.padding=0;
        globalDiv.style.margin=0; 
        
        globalDiv.style.width='100%';
        globalDiv.style.display='block';
        globalDiv.style.height=document.getElementsByTagName('body').item(0).clientHeight + 'px'; 
        globalDiv.style.backgroundColor='#aaa999';
        
        if(nohide==null)
        hideElementAll();
}
function dropGlobalDiv()
{
    try
    {
        document.getElementById('globalDiv').parentNode.removeChild(document.getElementById('globalDiv'));
        showElementAll();
    }
    catch(e){alert(e.message)}
}



//隐藏所有对象
function hideElementAll(){
    HideElement( 'SELECT' );
    HideElement( 'OBJECT' );
    HideElement( 'IFRAME' );
}

//隐藏主页面对象
function HideElement( strElementTagName ){
    try{
        for( i = 0 ; i < document.getElementsByTagName(strElementTagName).length ; i++ ){
            var objTemp =document.getElementsByTagName(strElementTagName)[i];
            objTemp.style.visibility = 'hidden';
        }
    }catch( e ){
        alert( e.message );
    }
}

//显示所有对象
function showElementAll(){
    ShowElement( 'SELECT' );
    ShowElement( 'OBJECT' );
    ShowElement( 'IFRAME' );
}
//显示主页面对象
function ShowElement( strElementTagName ){
    try{
        for( i = 0 ; i < document.getElementsByTagName(strElementTagName).length; i++ ){
            var objTemp = document.getElementsByTagName(strElementTagName)[i];
            objTemp.style.visibility = 'visible';
        }
    }catch( e ){
        alert( e.message );
    }
}