代码如下:
New Document function isreadonly(){
var obj = document.getElementById("username");
obj.setAttribute("readOnly",true);
obj.style.backgroundColor="#d2d2d2";
}
function readwrite(){
var obj = document.getElementById("username");
obj.setAttribute("readOnly",false);
obj.style.backgroundColor="#ffffff";
}
点击“read”按钮，input框不能书写，且变灰；点击“write”按钮，input框恢复。
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