//图片按比例缩放
var flag=false;
function DrawImage1(ImgD,width,height){
var image=new Image();
var iwidth = width; //定义允许图片宽度
var iheight = height; //定义允许图片高度
image.src=ImgD.src;

if(image.width>0 && image.height>0){
flag=true;
if(image.width/image.height>= iwidth/iheight){
if(image.width>iwidth){ 
ImgD.width=iwidth;
ImgD.height=(image.height*iwidth)/image.width;
}else{
ImgD.width=image.width; 
ImgD.height=image.height;
}

ImgD.alt=image.width+"×"+image.height;
}
else{
if(image.height>iheight){ 
ImgD.height=iheight;
ImgD.width=(image.width*iheight)/image.height; 
}else{
ImgD.width=image.width; 
ImgD.height=image.height;
}
ImgD.alt=image.width+"×"+image.height;
}
}
} 
function DrawImage2(ImgD,width,height){
var image=new Image();
var iwidth = width; //定义允许图片宽度
var iheight = height; //定义允许图片高度
image.src=ImgD.src;

if(image.width>0 && image.height>0){
flag=true;
if(image.width/image.height>= iwidth/iheight){
if(image.width>iwidth){ 
ImgD.style.width=iwidth;
ImgD.style.height=(image.height*iwidth)/image.width;
}else{
ImgD.width=image.width; 
ImgD.height=image.height;
}

ImgD.alt=image.width+"×"+image.height;
}
else{
if(image.height>iheight){ 
ImgD.style.height=iheight;
ImgD.style.width=(image.width*iheight)/image.height; 
}else{
ImgD.style.width=image.width; 
ImgD.style.height=image.height;
}
ImgD.alt=image.width+"×"+image.height;
}
}
} 

function setScope(obj,setW,setH) {
	var mainObj = document.getElementById(obj);
	var subObj = mainObj.getElementsByTagName("img");
	for (i=0;i<subObj.length;i++) {
		divW = subObj[i].width;
		divH = subObj[i].height;
		if (divW > divH) {
			if (divW > setW) {
				valW = setW;
				valH = parseInt(setW * divH / divW);		//目标高度
				if (valH > setH) {
					valH = setH;
					valW = parseInt(setH * valW / valH);	//目标宽度
				}
				subObj[i].style.width = valW + "px";
				subObj[i].style.height = valH + "px";
				subObj[i].style.marginTop = parseInt((setH - valH) / 2) + "px";
			}
		}
		else if (divH > divW) {
			if (divH > setH) {
				valH = setH;
				valW = parseInt(setH * divW / divH);		//目标宽度
				if (valW > setW) {
					valW = setW;
					valH = parseInt(setW * valH / valW);	//目标高度
				}
				subObj[i].style.height = valH + "px";
				subObj[i].style.width = valW + "px";
			}
		}
		else {
			if (divH < setH) {
				subObj[i].style.marginTop = parseInt((setH - divH) / 2) + "px";
			}
			else if (divH > setH) {
				val = setW - setH >= 0?setH:setW;
				subObj[i].style.width = subObj[i].style.height = val + "px";
				if (setH > val) {
					subObj[i].style.marginTop = parseInt((setH - val) / 2) + "px";
				}
			}
		}
	}
}
function DrawImage(obj,setW,setH) {
		divW = obj.width;
		divH = obj.height;
		if (divW > divH) {
			if (divW > setW) {
				valW = setW;
				valH = parseInt(setW * divH / divW);		//目标高度
				if (valH > setH) {
					valH = setH;
					valW = parseInt(setH * valW / valH);	//目标宽度
				}
				obj.style.width = valW + "px";
				obj.style.height = valH + "px";
				obj.style.marginTop = parseInt((setH - valH) / 2) + "px";
			}
		}
		else if (divH > divW) {
			if (divH > setH) {
				valH = setH;
				valW = parseInt(setH * divW / divH);		//目标宽度
				if (valW > setW) {
					valW = setW;
					valH = parseInt(setW * valH / valW);	//目标高度
				}
				obj.style.height = valH + "px";
				obj.style.width = valW + "px";
			}
		}
		else {
			if (divH < setH) {
			
				obj.style.marginTop = parseInt((setH - divH) / 2) + "px";
			}
			
			else if (divH > setH) {
			
				val = setW - setH >= 0?setH:setW;
				obj.style.width = obj.style.height = val + "px";
				if (setH > val) {
					obj.style.marginTop = parseInt((setH - val) / 2) + "px";
				}
			}
		}
}