A lock Layer

/**
* Create a covering layer
* Id: the id of the covering layer. If it is null, an id is automatically generated.
* CssObj: Specifies the style object of the covering layer. It can also be a class name.
* Opacity: a decimal point between 0 and 1, indicating transparency. The smaller the number, the higher the transparency.
*/
Function Lock (id, cssObj, opacity ){
Lock. num = Lock. num | 1;
Lock. num ++;
// The id of the current Hidden Layer
Var lockID = id | 'didlock _ '+ Lock. num;
// Default Style
CssObj = cssObj | {backgroundColor: "black", filter: "alpha (Opacity = 40)", opacity: "0.4", zIndex: "1 "};
If (opacity)
{
CssObj. opacity = opacity;
CssObj. filter = "alpha (Opacity =" + (opacity * 100) + ")";
}
// A short function of getElementById
Var $ = function (id) {document. getElementById (id );};
// If a Dom element with the same name already exists, this function is returned.
If ($ (id ))
{
This. success = false;
This. errorMsg = 'id repeated ';
Return;
}
Var divLock = document. createElement ("div ");
// Obtain the height of the current page
Var getBodyHeight = function ()
{
// For IE
If (document. all)
{
Return Math. max (document. body. scrollHeight, document.documentElement.scrollHeight,document.doc umentElement. clientHeight );
}
Return Math. max (document. body. scrollHeight, document.doc umentElement. scrollHeight );
};
DivLock. id = lockID;
DivLock. style. width = Math.max(document.body.scrollWidth,document.doc umentElement. scrollWidth) + "px"
DivLock. style. height = getBodyHeight () + "px ";
DivLock. style. position = "absolute ";
DivLock. style. top = "0px ";
DivLock. style. left = "0px ";
DivLock. style. display = "none ";
// DivLock. style. verticalAlign = "middle ";
SetClass (divLock, cssObj );
Document. body. appendChild (divLock );
This. div = divLock;
This. removed = false;
This. show = function (){
If (this. removed)
{
Return;
}
This. div. style. display = "block ";
};
This. hidden = function (){
If (this. removed)
{
Return;
}
This. div. style. display = "none ";
};
This. remove = function (){
This. div. parentNode. removeChild (this. div );
This. removed = true;
}
}