common.js

国外MPI教材

    } else if (!ele.value) {
        markClozeWord(ele, NOT_ATTEMPTED);
        return NOT_ATTEMPTED;
    } else {
        markClozeWord(ele, WRONG);
        return WRONG;
    }
}

// Marks a cloze question (at the moment just changes the color)
// 'mark' should be 0=Not Answered, 1=Wrong, 2=Right
function markClozeWord(ele, mark) {
    switch (mark) {
        case 0:
            // Not attempted
            ele.style.backgroundColor = "";
            break;
        case 1:
            // Wrong
            ele.style.backgroundColor = "red";
            break;
        case 2: 
            // Correct
            ele.style.backgroundColor = "lime";
            break;
    }
    return mark
}

// Return the last mark applied to a word
function getClozeMark(ele) {
    // Return last mark applied
    switch (ele.style.backgroundColor) {
        case 'red':   return 1; // Wrong
        case 'lime':  return 2; // Correct
        default:      return 0; // Not attempted
    }
}

// Decrypts and returns the answer for a certain cloze field word
function getClozeAnswer(ele) {
    var idents = getClozeIds(ele)
    var ident = idents[0]
    var inputId = idents[1]
    var answerSpan = document.getElementById('clozeAnswer'+ident+'.'+inputId);
    var code = answerSpan.innerHTML;
    code = decode64(code)
    code = unescape(code)
    // XOR "Decrypt"
    result = '';
    var key = 'X'.charCodeAt(0);
    for (var i=0; i<code.length; i++) {
        var letter = code.charCodeAt(i);
        key ^= letter
        result += String.fromCharCode(key);
    }
    return result
}

// Base64 Decode
// Base64 code from Tyler Akins -- http://rumkin.com
function decode64(input) {
   var keyStr = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=";
   var output = "";
   var chr1, chr2, chr3;
   var enc1, enc2, enc3, enc4;
   var i = 0;
   // Remove all characters that are not A-Z, a-z, 0-9, +, /, or =
   input = input.replace(/[^A-Za-z0-9\+\/\=]/g, "");
   do {
      enc1 = keyStr.indexOf(input.charAt(i++));
      enc2 = keyStr.indexOf(input.charAt(i++));
      enc3 = keyStr.indexOf(input.charAt(i++));
      enc4 = keyStr.indexOf(input.charAt(i++));

      chr1 = (enc1 << 2) | (enc2 >> 4);
      chr2 = ((enc2 & 15) << 4) | (enc3 >> 2);
      chr3 = ((enc3 & 3) << 6) | enc4;

      output = output + String.fromCharCode(chr1);

      if (enc3 != 64) {
         output = output + String.fromCharCode(chr2);
      }
      if (enc4 != 64) {
         output = output + String.fromCharCode(chr3);
      }
   } while (i < input.length);
   return output;
}

// Returns the corrected word or an empty string
function checkClozeWord(ele) {
    var guess = ele.value;
    // Extract the idevice id and the input number out of the element's id
    var original = getClozeAnswer(ele);
    var answer = original;
    var guess = ele.value
    var ident = getClozeIds(ele)[0]
    // Read the flags for checking answers
    var strictMarking = eval(document.getElementById(
        'clozeFlag'+ident+'.strictMarking').value);
    var checkCaps = eval(document.getElementById(
        'clozeFlag'+ident+'.checkCaps').value);
    if (!checkCaps) {
        guess = guess.toLowerCase();
        answer = original.toLowerCase();
    }
    if (guess == answer)
        // You are right!
        return original
    else if (strictMarking || answer.length <= 4)
        // You are wrong!
        return "";
    else {
        // Now use the similarity check algorythm
        var i = 0;
        var j = 0;
        var orders = [[answer, guess], [guess, answer]];
        var maxMisses = Math.floor(answer.length / 6) + 1;
        var misses = 0;
        if (guess.length <= maxMisses) {
            misses = Math.abs(guess.length - answer.length);
            for (i = 0; i < guess.length; i++ ) {
                if (answer.search(guess[i]) == -1) {
                    misses += 1;
                }
            }
            if (misses <= maxMisses) {
                return answer;
            } else {
                return "";
            }
        }
        // Iterate through the different orders of checking
        for (i = 0; i < 2; i++) {
            var string1 = orders[i][0];
            var string2 = orders[i][1];
            while (string1) {
                misses = Math.floor(
                            (Math.abs(string1.length - string2.length) +
                             Math.abs(guess.length - answer.length)) / 2)
                var max = Math.min(string1.length, string2.length)
                for (j = 0; j < max; j++) {
                    var a = string2.charAt(j);
                    var b = string1.charAt(j);
                    if (a != b)
                        misses += 1;
                    if (misses > maxMisses)
                        break;
                }
                if (misses <= maxMisses)
                    // You are right
                    return answer;
                string1 = string1.substr(1);
            }
        }
        // You are wrong!
        return "";
    }
}

// Extracts the idevice id and input id from a javascript element
function getClozeIds(ele) {
    // Extract the idevice id and the input number out of the element's id
    // id is "clozeBlank%s.%s" % (idevice.id, input number)
    var id = ele.id.slice(10); 
    var dotindex = id.indexOf('.')
    var ident = id.slice(0, dotindex)
    var inputId = id.slice(id.indexOf('.')+1)
    return [ident, inputId]
}

// Calculate the score for cloze idevice
function showClozeScore(ident, mark) {
    var score = 0
    var div = document.getElementById('cloze' + ident)
    var inputs = getCloseInputs(ident)
    for (var i=0; i<inputs.length; i++) {
        var input = inputs[i];
        if (mark) {
            var result = checkAndMarkClozeWord(input);
        } else {
            var result = getClozeMark(input);
        }
        if (result == 2) {
            score++;
        }
    }
    // Show it in a nice paragraph
    var scorePara = document.getElementById('clozeScore' + ident);
    scorePara.innerHTML = YOUR_SCORE_IS + score + "/" + inputs.length + ".";
}

// Returns an array of input elements that are associated with a certain idevice
function getCloseInputs(ident) {
    var result = new Array;
    var clozeDiv = document.getElementById('cloze'+ident)
    recurseFindClozeInputs(clozeDiv, ident, result)
    return result
}

// Adds any cloze inputs found to result, recurses down
function recurseFindClozeInputs(dad, ident, result) {
    for (var i=0; i<dad.childNodes.length; i++) {
        var ele = dad.childNodes[i];
        // See if it is a blank
        if (ele.id) {
            if (ele.id.search('clozeBlank'+ident) == 0) {
                result.push(ele);
                continue;
            }
        }
        // See if it contains blanks
        if (ele.hasChildNodes()) {
            recurseFindClozeInputs(ele, ident, result);
        }
    }
}
    

// Pass the cloze element's id, and the visible property of the feedback element
// associated with it will be toggled. If there is no feedback field, does
// nothing
function toggleClozeFeedback(ident) {
    var feedbackIdEle = document.getElementById(
        'clozeVar'+ident+'.feedbackId');
    if (feedbackIdEle) {
        var feedbackId = feedbackIdEle.value;
        toggleElementVisible(feedbackId);
    }
}

// Toggle the visiblity of an element from it's id
function toggleElementVisible(ident) {
    // Toggle the visibility of an element
    var element = document.getElementById(ident);
    if (element) {
        if (element.style.display != "none") {
            element.style.display = "none";
        } else {
            element.style.display = "";
        }
    }
}

// Reflection Idevice code ////////////////////////////////////////////////

// Show or hide the feedback for reflection idevice
function showAnswer(id,isShow) {
    if (isShow==1) {
        document.getElementById("s"+id).style.display = "block";
        document.getElementById("hide"+id).style.display = "block";
        document.getElementById("view"+id).style.display = "none";
    } else {
        document.getElementById("s"+id).style.display = "none";
        document.getElementById("hide"+id).style.display = "none";
        document.getElementById("view"+id).style.display = "block";
    }
}

//change forum or discussion topic or lms for discussion idevice.
function submitChange(action, selectId) 
{
    var form = document.getElementById("contentForm")      
    form.action.value = action
    var select = document.getElementById(selectId) 
    form.object.value = select.value;
    form.isChanged.value = 1;
    form.submit();
}


// show or hide the feedback for cloze idevice
function toggleFeedback(id) {
    var ele = document.getElementById('fb'+id);
    if (ele.style.display == "block") {
        ele.style.display = "none";
    } else {
        ele.style.display = "block";
    }
}

// Call the function like this:
//insertAtCursor(document.formName.fieldName, ‘this value’);
function insertAtCursor(myField, myValue, num) {
    //MOZILLA/NETSCAPE support
   
    if (myField.selectionStart || myField.selectionStart == '0') {
        var startPos = myField.selectionStart;
        var endPos = myField.selectionEnd;
        myField.value = myField.value.substring(0, startPos)
            + myValue
            + myField.value.substring(endPos, myField.value.length);
        myField.selectionStart = startPos + myValue.length - num
    } else {
        myField.value += myValue;
    } 
    myField.selectionEnd = myField.selectionStart
    myField.focus();
}

//used by maths idevice
function insertSymbol(id, string, num){
    var ele = document.getElementById(id);
    insertAtCursor(ele, string, num)
}

//used for multiple select idevice for calculating score and showing feedback.
function calcScore(num, ident){
    var score = 0;
    for(i=0; i<num; i++){
        var chkele = document.getElementById(ident+i.toString());        
        var ansele = document.getElementById("ans"+ident+i.toString())
        chk = "False"
        if (chkele.checked==1)
            chk = "True"   
        if (chk == chkele.value){
            score++
            ansele.style.color = "black"
        }else{            
            ansele.style.color = "red"
        }
    }
    var fele = document.getElementById("f"+ident)
    fele.style.display = "block"
    alert(YOUR_SCORE_IS  + score + "/" + num)
}

// used to show question's feedback for multi-select idevice 
function showFeedback(num, ident){
    for(i=0; i<num; i++){
        var ele = document.getElementById(ident+i.toString())
        var ele0 = document.getElementById(ident+i.toString()+"0")
        var ele1 = document.getElementById(ident+i.toString()+"1")
        var ansele = document.getElementById("ans"+ident+i.toString())
        chk = "False"
        if (ele.checked==1)
            chk = "True"   
        if (chk == ele.value){
            ele1.style.display = "block"
			ele0.style.display = "none"
            ansele.style.color = "black"
        }else{            
            ele0.style.display = "block"
			ele1.style.display = "none"
            ansele.style.color = "red"
        }
    }
    var fele = document.getElementById("f"+ident)
    fele.style.display = "block"
}


///////////////////////////////////////////////
// Media plugin detection codes, modified from:
// http://developer.apple.com/internet/webcontent/detectplugins.html
function detectQuickTime() {
    pluginFound = detectPlugin('QuickTime');
    return pluginFound;
}

function detectReal() {
    pluginFound = detectPlugin('RealPlayer');
     return pluginFound;
}

function detectFlash() {
    pluginFound = detectPlugin('Shockwave','Flash'); 
     return pluginFound;
}

function detectDirector() { 
    pluginFound = detectPlugin('Shockwave','Director'); 
     return pluginFound;
}


function detectWindowsMedia() {
    pluginFound = detectPlugin('Windows Media');
      return pluginFound;
}

function detectPlugin() {
    // allow for multiple checks in a single pass
    var daPlugins = detectPlugin.arguments;
    // consider pluginFound to be false until proven true
    var pluginFound = false;
    // if plugins array is there and not fake
    if (navigator.plugins && navigator.plugins.length > 0) {
	var pluginsArrayLength = navigator.plugins.length;
	// for each plugin...
	for (pluginsArrayCounter=0; pluginsArrayCounter < pluginsArrayLength; pluginsArrayCounter++ ) {
	    // loop through all desired names and check each against the current plugin name
	    var numFound = 0;
	    for(namesCounter=0; namesCounter < daPlugins.length; namesCounter++) {
		// if desired plugin name is found in either plugin name or description
		if( (navigator.plugins[pluginsArrayCounter].name.indexOf(daPlugins[namesCounter]) >= 0) || 
		    (navigator.plugins[pluginsArrayCounter].description.indexOf(daPlugins[namesCounter]) >= 0) ) {
		    // this name was found
		    numFound++;
		}   
	    }
	    // now that we have checked all the required names against this one plugin,
	    // if the number we found matches the total number provided then we were successful
	    if(numFound == daPlugins.length) {
		pluginFound = true;
		// if we've found the plugin, we can stop looking through at the rest of the plugins
		break;
	    }
	}
    }
    return pluginFound;
} // detectPlugin
///////////////////////////////////////////////