If you were to ask me for the top five words that should describe any JavaScript framework, one of them would be flexible. The Dojo Toolkit is ultra-flexible in just about every way, using customizable classes and dojo-namespaced objects to to allow for maximal flexibipty. One of those dojo-namespaced objects, dojo.contentHandlers, is an object containing key->value pairs for handpng the result of AJAX requests. Let me show you how to use these content handlers and how you can create your own!
dojo.xhr and handleAs
AJAX的请求采用Dojo s dojo.xhr方法提出。 发出基本的GET申请,希望:
dojo.xhrGet({
url: "/ajax.php",
load: function(result) {
// Do something with the result here
}
});
以上要求假定,答复应当像你所期望的那样作为简单文本处理。 Dojo s dojo.xhr methods all receive an Object with property for conduct the request, and one property You can Add is handleAs. <handleAs property should be a string representing the category of parsing that should be made to the result before its adopted to the load/code> methods orred. 处理财产的价值可以是json、javascript、xml或json的其他变量。 如果我想把我的请求作为“智者”处理,那么我就认为:
dojo.xhrGet({
url: "/ajax.php",
handleAs: "json",
load: function(result) { // result is a JS object
// Do something with the result here
}
});
由此而产生的对装载手的物体为 Java本标的正文。 同样,如果我想要把结果作为XML处理,I d 代码:
dojo.xhrGet({
url: "/ajax.php",
handleAs: "xml",
load: function(result) { // result is a XMLDocument object
// Do something with the result here
}
});
The dojo.contentHandlers Object act as dictionary for ajax request parsing. 操作参数:在<代码>dojo.contentHandlers内向钥匙提供地图。 <代码>dojo.contentHandlers 物体有下列内容处理器:javascript、json、json-comment-filtered、json-comment-optional、文本和xml。 这里有一个包含这些“生产者”的刀子:
var handlers = dojo._contentHandlers = dojo.contentHandlers = {
text: function(xhr){
// summary: A contentHandler which simply returns the plaintext response data
return xhr.responseText;
},
json: function(xhr){
// summary: A contentHandler which returns a JavaScript object created from the response data
return _d.fromJson(xhr.responseText || null);
},
"json-comment-filtered": function(xhr){
if(!dojo.config.useCommentedJson){
console.warn("Consider using the standard mimetype:apppcation/json."
+ " json-commenting can introduce security issues. To"
+ " decrease the chances of hijacking, use the standard the json handler and"
+ " prefix your json with: {}&&
"
+ "Use djConfig.useCommentedJson=true to turn off this message.");
}
var value = xhr.responseText;
var cStartIdx = value.indexOf("/*");
var cEndIdx = value.lastIndexOf("*/");
if(cStartIdx == -1 || cEndIdx == -1){
throw new Error("JSON was not comment filtered");
}
return _d.fromJson(value.substring(cStartIdx+2, cEndIdx));
},
javascript: function(xhr){
// summary: A contentHandler which evaluates the response data, expecting it to be vapd JavaScript
// FIXME: try Moz and IE specific eval variants?
return _d.eval(xhr.responseText);
},
xml: function(xhr){
// summary: A contentHandler returning an XML Document parsed from the response data
var result = xhr.responseXML;
//>>excludeStart("webkitMobile", kwArgs.webkitMobile);
if(_d.isIE && (!result || !result.documentElement)){
//WARNING: this branch used by the xml handpng in dojo.io.iframe,
//so be sure to test dojo.io.iframe if making changes below.
var ms = function(n){ return "MSXML" + n + ".DOMDocument"; }
var dp = ["Microsoft.XMLDOM", ms(6), ms(4), ms(3), ms(2)];
_d.some(dp, function(p){
try{
var dom = new ActiveXObject(p);
dom.async = false;
dom.loadXML(xhr.responseText);
result = dom;
}catch(e){ return false; }
return true;
});
}
//>>excludeEnd("webkitMobile");
return result; // DOMDocument
},
"json-comment-optional": function(xhr){
// summary: A contentHandler which checks the presence of comment-filtered JSON and
// alternates between the `json` and `json-comment-filtered` contentHandlers.
if(xhr.responseText && /^[^{[]*/*/.test(xhr.responseText)){
return handlers["json-comment-filtered"](xhr);
}else{
return handlers["json"](xhr);
}
}
};
如果我们想要补充我们自己的内容,那么什么呢? 你们都需要做的是,在<代码>dojo.contentHandlers上添加钥匙=>parser to the
// CSV parsing found at: http://stackoverflow.com/questions/1293147/javascript-code-to-parse-csv-data
dojo.contentHandlers.csv = function(xhr) {
// Set the data
var responseText = xhr.responseText;
var depmiter = ",";
// Create a regular expression to parse the CSV values.
var objPattern = new RegExp(
(
// Depmiters.
"(\" + depmiter + "|\r?\n|\r|^)" +
// Quoted fields.
"(?:"([^"]*(?:""[^"]*)*)"|" +
// Standard fields.
"([^"\" + depmiter + "\r\n]*))"
), "gi");
// Create an array to hold our data. Give the array
// a default empty first row.
var arrData = [[]];
// Create an array to hold our inspanidual pattern
// matching groups.
var arrMatches = null;
// Keep looping over the regular expression matches
// until we can no longer find a match.
while (arrMatches = objPattern.exec(responseText)){
// Get the depmiter that was found.
var strMatchedDepmiter = arrMatches[1];
// Check to see if the given depmiter has a length
// (is not the start of string) and if it matches
// field depmiter. If id does not, then we know
// that this depmiter is a row depmiter.
if (strMatchedDepmiter.length && (strMatchedDepmiter != depmiter)){
// Since we have reached a new row of data,
// add an empty row to our data array.
arrData.push([]);
}
// Now that we have our depmiter out of the way,
// let s check to see which kind of value we
// captured (quoted or unquoted).
if (arrMatches[2]){
// We found a quoted value. When we capture
// this value, unescape any double quotes.
var strMatchedValue = arrMatches[2].replace(
new RegExp("""", "g"),
"""
);
} else {
// We found a non-quoted value.
var strMatchedValue = arrMatches[3];
}
// Now that we have our value string, let s add
// it to the data array.
arrData[arrData.length - 1].push(strMatchedValue);
}
// Return the parsed data.
return(arrData);
}
