AJAX=Asynchronous JavaScript and XML<\/p>\n
AJAX\u662f\u5728\u4e0d\u91cd\u65b0\u52a0\u8f7d\u6574\u4e2a\u9875\u9762\u7684\u60c5\u51b5\u4e0b\u4e0e\u670d\u52a1\u5668\u4ea4\u6362\u6570\u636e\u5e76\u66f4\u65b0\u90e8\u5206\u7f51\u9875\u7684\u827a\u672f\uff0c\u662f\u4e00\u79cd\u7528\u4e8e\u521b\u5efa\u5feb\u901f\u52a8\u6001\u7f51\u9875\u7684\u6280\u672f\u3002<\/p>\n
XMLHttpRequest \u662fAJAX\u7684\u57fa\u7840,\u73b0\u4ee3\u6240\u6709\u6d4f\u89c8\u5668\u5747\u652f\u6301XMLHttpRequest\u5bf9\u8c61\uff08IE5\u3001IE6\u4f7f\u7528ActiveXObject\uff09\u3002<\/p>\n
\u521b\u5efaXMLHttpRequest\u5bf9\u8c61\u7684\u8bed\u6cd5\uff1avariable=new XMLHttpRequest();<\/p>\n
\u5411\u670d\u52a1\u5668\u53d1\u9001\u8bf7\u6c42\uff1a\u4f7f\u7528XMLHttpRequest \u5bf9\u8c61\u7684 open() \u548c send() \u65b9\u6cd5\uff1a<\/p>\n
xmlhttp.open(method,url,async);<\/p>\n
xmlhttp.send(); send(string )\u5c06\u8bf7\u6c42\u53d1\u9001\u5230\u670d\u52a1\u5668\uff0cstring\u4ec5\u7528\u4e8ePOST\u8bf7\u6c42<\/p>\n
<\/p>\n
method:\u8bf7\u6c42\u7684\u7c7b\u578b\uff1bGET\u6216POST<\/p>\n
URL:\u6587\u4ef6\u5728\u670d\u52a1\u5668\u4e0a\u7684\u4f4d\u7f6e<\/p>\n
async\uff1atrue\uff08\u5f02\u6b65\uff09false\uff1a\uff08\u540c\u6b65\uff09<\/p>\n
\u4e3a\u4e86\u907f\u514dget\u5230\u7684\u662f\u7f13\u5b58\u7684\u7ed3\u679c\uff0c\u8bf7\u5411 URL \u6dfb\u52a0\u4e00\u4e2a\u552f\u4e00\u7684 ID\uff1a<\/p>\n
xmlhttp.open(“GET”,”demo_get.asp?t=” + Math.random(),true);<\/p>\n
xmlhttp.send();<\/p>\n
\u5982\u679c\u9700\u8981\u50cf HTML \u8868\u5355\u90a3\u6837 POST \u6570\u636e\uff0c\u8bf7\u4f7f\u7528 setRequestHeader() \u6765\u6dfb\u52a0 HTTP \u5934\u3002\u7136\u540e\u5728 send() \u65b9\u6cd5\u4e2d\u89c4\u5b9a\u60a8\u5e0c\u671b\u53d1\u9001\u7684\u6570\u636e\uff1a<\/p>\n
xmlhttp.open(“POST”,”ajax_test.asp”,true);<\/p>\n
xmlhttp.setRequestHeader(“Content-type”,”application\/x-www-form-urlencoded”);<\/p>\n
xmlhttp.send(“fname=Bill&lname=Gates”);<\/p>\n
setRequestHeader(header,value)\u5411\u8bf7\u6c42\u6dfb\u52a0 HTTP \u5934\u3002header: \u89c4\u5b9a\u5934\u7684\u540d\u79f0 value: \u89c4\u5b9a\u5934\u7684\u503c<\/p>\n
\u5f53\u4f7f\u7528 async=true \u65f6\uff0c\u8bf7\u89c4\u5b9a\u5728\u54cd\u5e94\u5904\u4e8e onreadystatechange \u4e8b\u4ef6\u4e2d\u7684\u5c31\u7eea\u72b6\u6001\u65f6\u6267\u884c\u7684\u51fd\u6570\uff1a<\/p>\n
xmlhttp.onreadystatechange=function()<\/p>\n
{<\/p>\n
if (xmlhttp.readyState==4 && xmlhttp.status==200)<\/p>\n
{<\/p>\n
document.getElementById(“myDiv”).innerHTML=xmlhttp.responseText;<\/p>\n
}<\/p>\n
}<\/p>\n
xmlhttp.open(“GET”,”test1.txt”,true);<\/p>\n
xmlhttp.send();<\/p>\n
\u670d\u52a1\u5668\u54cd\u5e94<\/p>\n
\u5982\u9700\u83b7\u5f97\u6765\u81ea\u670d\u52a1\u5668\u7684\u54cd\u5e94\uff0c\u8bf7\u4f7f\u7528 XMLHttpRequest \u5bf9\u8c61\u7684 responseText \u6216 responseXML \u5c5e\u6027\u3002<\/p>\n
responseText \u83b7\u5f97\u5b57\u7b26\u4e32\u5f62\u5f0f\u7684\u54cd\u5e94\u6570\u636e\u3002<\/p>\n
responseXML \u83b7\u5f97 XML \u5f62\u5f0f\u7684\u54cd\u5e94\u6570\u636e\u3002<\/p>\n
onreadystatechange \u4e8b\u4ef6<\/p>\n
readyState \u5c5e\u6027\u5b58\u6709 XMLHttpRequest \u7684\u72b6\u6001\u4fe1\u606f\u3002\u6bcf\u5f53 readyState \u6539\u53d8\u65f6\uff0c\u5c31\u4f1a\u89e6\u53d1 onreadystatechange \u4e8b\u4ef6\u3002<\/p>\n
onreadystatechange \u5b58\u50a8\u51fd\u6570\uff08\u6216\u51fd\u6570\u540d\uff09\uff0c\u6bcf\u5f53 readyState \u5c5e\u6027\u6539\u53d8\u65f6\uff0c\u5c31\u4f1a\u8c03\u7528\u8be5\u51fd\u6570\u3002<\/p>\n
readyState \u5b58\u6709 XMLHttpRequest \u7684\u72b6\u6001\u3002\u4ece 0 \u5230 4 \u53d1\u751f\u53d8\u5316\u3002\uff080: \u8bf7\u6c42\u672a\u521d\u59cb\u53161: \u670d\u52a1\u5668\u8fde\u63a5\u5df2\u5efa\u7acb2: \u8bf7\u6c42\u5df2\u63a5\u65363: \u8bf7\u6c42\u5904\u7406\u4e2d4: \u8bf7\u6c42\u5df2\u5b8c\u6210\uff0c\u4e14\u54cd\u5e94\u5df2\u5c31\u7eea\uff09<\/p>\n
status 200: “OK” 404: \u672a\u627e\u5230\u9875\u9762<\/p>\n
\u5f53 readyState \u7b49\u4e8e 4 \u4e14\u72b6\u6001\u4e3a 200 \u65f6\uff0c\u8868\u793a\u54cd\u5e94\u5df2\u5c31\u7eea<\/p>\n
\u6b22\u8fce\u5206\u4eab\u672c\u6587\uff0c\u8f6c\u8f7d\u8bf7\u4fdd\u7559\u51fa\u5904\uff1a\u524d\u7aefABC<\/a> » AJAX\u77e5\u8bc6\u70b9\u56de\u987e<\/a><\/p>","protected":false},"excerpt":{"rendered":" AJAX=Asynchronous JavaScript and XML AJAX\u662f\u5728\u4e0d\u91cd\u65b0\u52a0\u8f7d\u6574\u4e2a\u9875\u9762\u7684\u60c5\u51b5\u4e0b\u4e0e\u670d\u52a1\u5668\u4ea4\u6362\u6570\u636e\u5e76\u66f4\u65b0\u90e8\u5206\u7f51\u9875\u7684\u827a\u672f\uff0c\u662f\u4e00\u79cd\u7528\u4e8e\u521b\u5efa\u5feb\u901f\u52a8\u6001\u7f51\u9875\u7684\u6280\u672f\u3002 XMLHttp […]<\/p>\n","protected":false},"author":1,"featured_media":112,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[3],"tags":[8],"_links":{"self":[{"href":"http:\/\/www.qdabc.cn\/index.php?rest_route=\/wp\/v2\/posts\/1002"}],"collection":[{"href":"http:\/\/www.qdabc.cn\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/www.qdabc.cn\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/www.qdabc.cn\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/www.qdabc.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=1002"}],"version-history":[{"count":1,"href":"http:\/\/www.qdabc.cn\/index.php?rest_route=\/wp\/v2\/posts\/1002\/revisions"}],"predecessor-version":[{"id":1003,"href":"http:\/\/www.qdabc.cn\/index.php?rest_route=\/wp\/v2\/posts\/1002\/revisions\/1003"}],"wp:featuredmedia":[{"embeddable":true,"href":"http:\/\/www.qdabc.cn\/index.php?rest_route=\/wp\/v2\/media\/112"}],"wp:attachment":[{"href":"http:\/\/www.qdabc.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1002"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/www.qdabc.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=1002"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/www.qdabc.cn\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=1002"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}