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error: function( msg ) {//Declaration error
throw msg;
},
parseJSON: function( data ) {//Convert the string to json format
if ( typeof data !== "string" || !data ) {//First determine whether it exists and whether it is a string
return null;
}
data = jQuery.trim( data );//Remove the before and after Blank
if ( window.JSON && window.JSON.parse ) {//The advanced version has native JSON conversion function window.JSON
return window.JSON.parse( data );
}
if ( rvalidchars.test( data.replace( rvalidescape, "@" )//
.replace( rvalidtokens, "]" )//
.replace( rvalidbraces, "")) ) {//Perform a simple Test, {true:1},{"a",{}}....all pass
//rvalidchars = /^[],:{}s]*$/,
//rvalidescape = /\(?:["\/bfnrt]|u[0-9a-fA-F]{4})/g,u[0-9a-fA-F]{4} matches Chinese, English and escape characters
//rvalidtokens = /"[^"\nr]*"|true|false|null|-?d (?:.d*)?(?:[eE][ -]?d )?/g ,//The matching string does not contain "", "
", "
”, Boolean value, null, number
//rvalidbraces = /(?:^|:|,)(?:s*[) /g, match (starting with empty or: or,) (followed by zero or Multiple spaces, followed by [) at the end such as [,: [,,[,, [etc.
return (new Function( "return " data ))();
}
jQuery.error( " Invalid JSON: " data );
},
parseXML: function( data , xml , tmp ) {I don’t understand the use of incoming xml tmp
if ( window.DOMParser ) { // Standard
/ The /DOMParser object parses XML text and returns an XML Document object. To use DOMParser, instantiate it using the constructor without parameters, and then call its //parseFromString() method:
tmp = new DOMParser();
xml = tmp.parseFromString( data , "text/xml" );
} else { // IE
xml = new ActiveXObject( "Microsoft.XMLDOM" );
xml.async = "false ";
xml.loadXML( data );
}
tmp = xml.documentElement;
if ( ! tmp || ! tmp.nodeName || tmp.nodeName === "parsererror" ) {//Determine whether the returned result is empty, not a node, and whether an error is reported
jQuery.error( "Invalid XML: " data );
}
return xml;
}
globalEval : function( data ) {//Make data executable
if ( data && rnotwhite.test( data ) ) {//Check whether it exists and not empty
( window.execScript || function( data ) {
window[ "eval" ].call( window, data );//window.eval.call(window,data) In some cases, the context cannot be changed in IE, so only Can use window.execScript for IE, other browsers use window.eval.call(window,data);
} )( data );
}
},
nodeName: function( elem, name ) {
return elem.nodeName && elem.nodeName.toUpperCase() === name.toUpperCase();//Determine whether it is a node. The node name is uppercase by default. In order to ensure correct judgment, all are converted into the same Format (uppercase)
},
each: function( object, callback, args ) {
var name, i = 0,
length = object.length,//window,String,Function, Array type is not undefined;..
isObj = length === undefined || jQuery.isFunction( object );//Mainly to distinguish objects and arrays
if ( args ) {//If not passed When entering parameters, the default name and value will be used as parameters. If there are parameters, the passed parameters will be used
if ( isObj ) {
for ( name in object ) {
if ( callback.apply( object[ name ], args ) === false ) {
break;
}
}
} else {
for ( ; i < length; ) {
if ( callback.apply( object[ i ], args ) === false ) {
break;
}
}
}
} else {//If no parameters are passed in,
if ( isObj ) {
for ( name in object ) {// The object[ name ] value is used as the current object, and the name and value are used as parameters
if ( callback.call( object[ name ], name, object[ name ] ) === false ) {//Judge the return value of the callback function and decide whether to continue the loop
break;
}
}
} else {
for ( ; i < length ; ) {//object[ i ] value as the current object, name (i is the order) and value as parameters
if ( callback.call( object[ i ], i, object[ i ] ) === false ) {//Judge the return value of the callback function and decide whether to continue the loop
break;
}
}
}
}
return object;
},
trim: trim ?//Detect whether there is a native trim method, if the parameter text! = intercepts the front and rear blanks, otherwise it returns empty. If there is no native trim, force conversion to a string and then perform regular replacement. Otherwise, an error is reported and regular replacement is used (trimLeft = /^s /,//matches the left blank, trimRight = /s $/,//match right blank),
function( text ) {
return text == null ?
"" :
trim.call( text );
} :
function( text ) {
return text == null ?
"" :
text.toString().replace( trimLeft, "" ).replace( trimRight, "" );
} ,