function ckbook(){
	var obj=document.getElementById;
	if(obj("title").value==""||obj("title").value.length<4){alert("Please fill in the full title of!");obj("title").focus();return false;}	
	if(obj("name").value==""||obj("name").value.length<4){alert("Please fill in your name!");obj("name").focus();return false;}
	if(obj("tel").value==""||obj("tel").value.length<8){alert("Please fill in your phone!");obj("tel").focus();return false;}
		
}
function sou(){
	var obj=document.getElementById;
	if(obj("sou").value==""||obj("sou").value.length<2){alert("Please fill in the elements you want to search the contents of the!");obj("sou").focus();return false;}			
}

function changeImg(mypic){ 
    var w=500; 
    var width = mypic.width; 
    var height = mypic.height; 
    var bili = width/height;         
        
    if(w<width) 
    { 

            mypic.width=w; 
            mypic.height=w/bili; 
    } 
}