js+ajax全选，反选，删除

js函数：

<SCRIPT language="javascript">
//JavaScript Document
function allcheck(form){
    var leng = form.chk.length;
    if(leng == undefined){//如果变量leng没有被初始化，默认为undefined
        if(!form.chk.checked){
            form.chk.checked = true;
        }
    }else{//否则为数组时
        for(i=0;i <leng;i++){
            if(!form.chk[i].checked){
                form.chk[i].checked = true;
            }
        }
    }
    return false;
}
function overcheck(){
    var leng = form.chk.length;
    if(leng == undefined){
        if(!form.chk.checked){
            form.chk.checked = true;
        }else{
            form.chk.checked = false;
        }
    }else{
        for(i = 0;i < leng;i++){
            if(!form.chk[i].checked){
                form.chk[i].checked = true;
            }else{
                form.chk[i].checked = false;
            }
        }
    }
    return false;
}

function GetXmlHttpObject(){ //封装一个兼容浏览器的ajax函数
  if(window.XMLHttpRequest){
      xmlHttp=new XMLHttpRequest();
    if(xmlHttp.overrideMimeType){
        xmlHttp.overrideMimeType("text/xml");
    }
   }else if(window.ActiveXObject){                 
    try{
        xmlHttp=new ActiveXObject("Msxml2.XMLHttp");
    }
    catch(e){
      try{
          xmlHttp=new ActiveXobject("Microsoft.XMLHttp");
      }
      catch(e){
          alert("您的浏览器不支持AJAX！");
          return false;
      }
     }
   }
  return xmlHttp;
}
var xmlHttp=GetXmlHttpObject();
function del(form){
    if(!window.confirm('是否要删除数据??')){  //弹出一个对话框，如果是就往下执行，否则停止
    }else{
        var leng = form.chk.length;
        if(leng == undefined){
            if(!form.chk.checked){
                alert('请选择你要删除的数据！');
            }else{
                xmlHttp = GetXmlHttpObject();//调用函数GetXmlHttpObject()
                var rd = form.chk.value;
                var url = 'mistake_delete.php?rd='+rd+'&del=allDel';
                xmlHttp.open("GET",url,true);
                xmlHttp.onreadystatechange = delnow;//处理的函数delnow
                xmlHttp.send(null);
            }
        }else{
            var leng = form.chk.length;
            var rd = new Array();
            var j = 0;
            for( var i = 0; i < leng; i++){
                if(form.chk[i].checked){
                rd[j++] = form.chk[i].value;
                }
            }if(rd == ''){
             window.alert('请选择你要删除的数据！');
            }else{
                xmlHttp = GetXmlHttpObject();
                var url = 'mistake_delete.php?rd='+rd+'&del=allDel';
                xmlHttp.open("GET",url,true);
                xmlHttp.onreadystatechange = delnow;
                xmlHttp.send(null);
            }
        }
    }
    return false;
}
function delnow(){
    if(xmlHttp.readyState == 4){
        if(xmlHttp.status == 200){
         var msg = xmlHttp.responseText;       
         if(msg != '1'){
          window.alert('删除失败!Error:'+msg);
         }else{
             window.alert('删除成功');
             window.location.href="mistake_list.php?page=1";
         }
        }
    }
}
function resultDel(){
    if(xmlHttp.readyState == 4){
        if(xmlHttp.status == 200){
      var msg = xmlHttp.responseText;       
         if(msg != '1'){
          window.alert('删除失败!Error:'+msg);
         }else{
             window.location.href="mistake_list.php?page=1";
         }
        }
    }
}
function del_single(rd){
 var url = 'mistake_delete.php?id='+rd+'&del=oneDel';
     xmlHttp.open("GET",url,true);
     xmlHttp.onreadystatechange = resultDel;//处理的函数delnow
     xmlHttp.send(null);
     window.alert('删除成功');
}
</SCRIPT>

HTML页面调用：

    <INPUT type="checkbox" name="chk[]" id="chk" value="{ff:$result[item].MISTAKEID/}">

    <button onClick="return del_single({ff:$result[item].MISTAKEID/})">单个删除</button>

    <button onClick="return allcheck(form);">全选</button>
    <button onClick="return overcheck(form);">反选</button>
    <button onClick="return del(form)">删除选中</button>

PHP处理页面：

$rdd = trim($_GET['rd']);

//全选删除
if(!empty($rdd) && $del = "allDel"){
 $arr_id = explode(",",$rdd);  //explode函数是把字符串分裂为一个数组
 foreach($arr_id as $key=>$val){  //不确定是单选还是多选，这里使用一个foreach循环
     $delete = $dbh->exec ( "DELETE FROM mistake WHERE mistakeId = '$val'" );
 }
 $reback = '0';
 if($delete){
     $reback = '1';
 }else{
     $reback = '2';
 }
 echo $reback;
}

// 独立删除

if(!empty($id) && $del = "oneDel"){
 $sub = $dbh->exec ( "DELETE FROM mistake WHERE mistakeId = '$id'" );
 $reback2 = '0';
 if($sub){
     $reback2 = '1';
 }else{
     $reback2 = '2';
 }
 echo $reback2;
}