未将对象引用设置为对象的实例.-我的复选框数组为空值 [英] Object reference not set to an instance of an object.-i got null value of checkbox array

问题描述

public CheckBox[] cb = null;
int z=0;
protected void Page_Load(object sender, EventArgs e)
{
    if (!IsPostBack)
        {
        cb = new CheckBox[count - k];
        //Database code.........
        while (dr.Read())//read data from access database
                {
            cb[z] = new CheckBox();
                    cb[z].Text = dr["Member_Name"].ToString();
                        Panel2.Controls.Add(cb[z]);
                        Panel2.Controls.Add(new LiteralControl("</br>"));
                        z = z + 1;
        }
    }
}
protected void Button6_Click(object sender, EventArgs e)
{
        for (int x = 0; x < cb.Length; x++)//ERROR IS HERE:Object reference not set to an instance of an object.
        {
        //processing check boxes    
    }
}

推荐答案

从错误消息中看来，这是:

From the error message it appears that this:

cb = new CheckBox[count - k];

永远不会被打电话.尝试设置断点和/或在下一行显示一条消息，以确保调用了该函数并初始化了数组.

never gets called. Try setting a breakpoint and/or displaying a message in the next line to make sure that the function is called and the array gets initialized.

请在调试时检查Button6_Click(). />
我确定cb [CheckBox]必须为null.那么length属性在那里无效，从而引发错误.

please Check the Button6_Click() while debugging.

I''m sure cb[CheckBox] must be null. then the length property invalid there, so that it throws the error.

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