[JS]jQuery中attr和prop方法的区别

前端开发作者： 2024-08-25 18:10:01

相比attr，prop是1.6.1才新出来的，两者从中文意思理解，都是获取/设置属性的方法（attributes和properties）。只是，window或document中使用.attr()方法在jQuery1.6之前不能正常运行，因为window和document中不能有attributes。

attr: function( elem, name, value, pass ) {
var ret, hooks, notxml,
nType = elem.nodeType;
// don't get/set attributes on text,comment and attribute nodes
if ( !elem || nType === 3 || nType === 8 || nType === 2 ) {
return;
}
if ( pass && jQuery.isFunction( jQuery.fn[ name ] ) ) {
return jQuery( elem )[ name ]( value );
}
// Fallback to prop when attributes are not supported
if ( typeof elem.getAttribute === "undefined" ) {
return jQuery.prop( elem, value );
}
notxml = nType !== 1 || !jQuery.isXMLDoc( elem );
// All attributes are lowercase
// Grab necessary hook if one is defined
if ( notxml ) {
name = name.toLowerCase();
hooks = jQuery.attrHooks[ name ] || ( rboolean.test( name ) ? boolHook : nodeHook );
}
if ( value !== undefined ) {
if ( value === null ) {
jQuery.removeAttr( elem, name );
return;
} else if ( hooks && "set" in hooks && notxml && (ret = hooks.set( elem, name )) !== undefined ) {
return ret;
} else {
elem.setAttribute( name, value + "" );
return value;
}
} "get" in hooks && notxml && (ret = hooks.get( elem, name )) !== null ) {
return ret;
} else {
ret = elem.getAttribute( name );
// Non-existent attributes return null,we normalize to undefined
return ret === null ?
undefined :
ret;
}
}

prop: ) {
// don't get/set properties on text,85); font-weight:bold; background:transparent">return;
}
notxml = nType !== 1 || !jQuery.isXMLDoc( elem );
if ( notxml ) {
// Fix name and attach hooks
name = jQuery.propFix[ name ] || name;
hooks = jQuery.propHooks[ name ];
}
if ( value !== undefined ) {
in hooks && (ret = hooks.set( elem,85); font-weight:bold; background:transparent">else {
return ( elem[ name ] = value );
}
} else {
in hooks && (ret = hooks.get( elem,85); font-weight:bold; background:transparent">null ) {
return elem[ name ];
}
}
}