在java脚本中读取文件时未定义

Undefined while reading file in java script

本文关键字：文件未定义读取 java 脚本更新时间：2023-09-26

以下代码不工作:<br/>

我尝试使用Visual Studio调试。我在this.result附近得到undefined。

我尽了最大的努力去找出错误，但什么也没找到。

<body>
    <br />
    <br /><br />
<br />
    <table align="center">
        <tr>
        <td>Number Of Nodes:</td>
        <td>&nbsp;&nbsp;<input id="num" type="text" style="width:30px"/></td>
            </tr><tr></tr>
<tr></tr>
        <tr>
            <td>
                Adjacancy Matrix:
            </td>
        <td>
            <input id="File1" type="file" />
            </td>
        </tr><tr></tr><tr></tr>
        <tr>
        <td>Node List Information:</td>
            <td>
        <input id="File2" type="file" />
        </td>
            </tr><tr></tr><tr></tr>
        <tr>
            <td>
        Stopping Condition:</td>
            <td>
        <input id="File3" type="file" /></td>
            </tr><tr></tr><tr></tr>
        <tr>
            <td>
        Algorithm:</td>
            <td>
        <input id="bfs" type="radio" name="algo" value="BFS" />BFS&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;
        <input id="dfs" type="radio" name="algo" value="DFS" />DFS</td>
            </tr><tr></tr><tr></tr><tr></tr>
<tr></tr><tr></tr>
<tr></tr>
        <tr></tr>
        <tr></tr>
        <tr>
            <td></td>
            <td>
        <button id="complete" type="submit" value="Complete" onclick="completeClick()">Complete Traversal</button></td>
            <td>
        <button id="step" type="submit">Step-By-Step Traversal</button>
<script type="text/javascript">
    var temp;
    var line;
    var vis;
    var numofnodes;
    function completeClick() {
        numofnodes = parseInt(document.getElementById('num').value, 10);
        temp = new Array(numofnodes);
        vis = new Array(numofnodes);
        document.getElementById('File1').onchange = function () {
            var file = this.files[0];
            var reade = new FileReader();
            reade.onload = function (e) {
                var lines = this.result.toString().split(''n');
                for (var x = 0; x < lines.length; x++) {
                    var tmp = lines[x].toString().split(' ');
                    for (var m = 0; m < tmp.length; m++) {
                        temp[x][m] = tmp[m];
                    }
                }
            };
            reade.readAsText(file);
        };
        document.getElementById('File2').onchange = function () {
            var file = this.files[0];
            var reade1 = new FileReader();
            reade1.onload = function (e) {
                line = this.result.toString().split(''n');
            };
            reade1.readAsText(file);
        };
        document.getElementById('print').innerHTML = "";
        if (document.getElementById('bfs').checked) {
            bfs(0);
        }
        else if (document.getElementById('dfs').checked) {
            dfs(0);
        }
    };
    function bfs(s) {
        var queue = [];
        for (var b = 0; b < numofnodes; b++) {
            queue[b] = [];
        }
        var i, front, rear, root;
        front = 0;
        rear = 0;
        vis[s] = 1;
        print(s);
        queue[rear+1] = s;
        while(front!=rear)
        {
            root = queue[front];
            for(i=0;i<numofnodes;i++)
            {
                if(temp[root,i]!=0 && vis[i]===0)
                {
                    vis[i] = 1;
                    queue[rear+1] = i;
                    print(i);
                }
            }
            front+=1;
        }
    };
    function dfs(i) {
        var j;
        vis[i] = 1;
        print(i);
        for (j = 0; j < numofnodes; j++) {
            if (vis[j] ===0) {
                if (temp[i][j] === 1) {
                    dfs(j);
                }
            }
        }
    };
    function print(i) {
        document.getElementById('print').innerHTML += line[i].toString() + "<br/>";
    };
</script>
            </td>
            </tr>
        <tr><td id="print" class="print"></td></tr>
    </table>
</body>
</html>

var temp是undefined

下面的更改(额外的2行-查找注释)应该可以修复它

    document.getElementById('File1').onchange = function () {
        var file = this.files[0];
        var reade = new FileReader();
        reade.onload = function (e) {
            temp = []; // add this line
            var lines = this.result.toString().split(''n');
            for (var x = 0; x < lines.length; x++) {
                var tmp = lines[x].toString().split(' ');
                temp[x] = []; // add this line too
                for (var m = 0; m < tmp.length; m++) {
                    temp[x][m] = tmp[m];
                }
            }
        };
        reade.readAsText(file);
    };