Javascript调用类函数

时间:2010-11-25 12:45:17

标签: javascript class function scope

我正在尝试调用类函数:

// Gantt chart object
function ganttChart(gContainerID) {

    this.isDebugMode = true;                                    // Is this chart in debug mode
    this.gContainer = document.getElementById(gContainerID);    // The container the chart is built inside
    this.gDebugPannel;                                          // Debug pannel

    // Create debug pannel
    if (this.isDebugMode) {
        this.gContainer.innerHTML += "<div id=\"gDebug" + gContainerID + "\" class=\"gDebug\">cometishian</div>";
        this.gDebugPannel = document.getElementById("gDebug" + gContainerID);
    }

    gDebug("lmfao!");

// Updates debug information
function gDebug(debugMessage) {
    alert(this.gDebugPannel.innerHTML);
    if (this.isDebugMode) { this.gDebugPannel.innerHTML = debugMessage; }
}
}

我希望它提醒“彗星”,但this.gDebugPannel.innerHTML是空的,有什么想法吗?

经过进一步调查,this.gDebugPannel未定义。

更新

// Gantt chart object
function ganttChart(gContainerID) {

    this.isDebugMode = true;                                    // Is this chart in debug mode
    this.gContainer = document.getElementById(gContainerID);    // The container the chart is built inside
    this.gDebugPannel;                                          // Debug pannel
    this.gPosX;
    this.gPosY;

    // Create debug pannel
    if (this.isDebugMode) {
        this.gContainer.innerHTML += "<div id=\"gDebug" + gContainerID + "\" class=\"gDebug\">5,5 | 5.1</div>";
        this.gDebugPannel = document.getElementById("gDebug" + gContainerID);
    }

    // Updates debug information
    ganttChart.gDebug = function(debugMessage) {
        if (this.isDebugMode) { this.gDebugPannel.innerHTML = debugMessage; }
    }

    this.gDebug("wo");

}

这行.Debug(“wo”)抛出:

网页错误详情

用户代理:Mozilla / 4.0(兼容; MSIE 8.0; Windows NT 5.1; Trident / 4.0; InfoPath.1; .NET CLR 2.0.50727; .NET CLR 3.0.04506.648; .NET CLR 3.5.21022; .NET CLR 1.1.4322; .NET CLR 3.0.4506.2152; .NET CLR 3.5.30729; OfficeLiveConnector.1.4; OfficeLivePatch.1.3) 时间戳:星期四,2010年11月25日12:57:51 UTC

Message: Object doesn't support this property or method
Line: 21
Char: 5
Code: 0
URI: http://server1/bb/ganttnew/gMain.js

2 个答案:

答案 0 :(得分:1)

您需要在this实例上调用该函数,如下所示:

gDebug.call(this, "Hi!");

正确的方法是将函数放在类原型中:(这应该在声明构造函数之后完成)

ganttChart.prototype.gDebug = function(debugMessage) {
    alert(this.gDebugPannel.innerHTML);
    if (this.isDebugMode) { this.gDebugPannel.innerHTML = debugMessage; }
}

this.gDebug("Hi!");

答案 1 :(得分:1)

你也可以这样做

this.gDebug= function(debugMessage) {
    alert(this.gDebugPannel.innerHTML);
    if (this.isDebugMode) { this.gDebugPannel.innerHTML = debugMessage; }
}