Question

http://www.c-sharpcorner.com/uploadfile/mgold/printingw2form09162005061136am/printingw2form.aspx

       for (int i = 0; i < this.Controls.Count; i++)
        {
            // Check if its a TextBox type by comparing to the type of one of the textboxes
            if (Controls[i].GetType() == this.Wages.GetType())
            {
                // Unbox the Textbox
                TextBox theText = (TextBox)Controls[i];
                // Draw the textbox string at the position of the textbox on the form, scaled to the print page
                g.DrawString(theText.Text, theText.Font, Brushes.Black, theText.Bounds.Left * scalex, theText.Bounds.Top * scaley, new StringFormat());
            }
            if (Controls[i].GetType() == this.RetirementPlanCheck.GetType())
            {
                // Unbox the Checkbox
                CheckBox theCheck = (CheckBox)Controls[i];
                // Draw the checkbox rectangle on the form scaled to the print page
                Rectangle aRect = theCheck.Bounds;
                g.DrawRectangle(aPen, aRect.Left * scalex, aRect.Top * scaley, aRect.Width * scalex, aRect.Height * scaley);
                // If the checkbox is checked, Draw the x inside the checkbox on the form scaled to the print page
                if (theCheck.Checked)
                {
                    g.DrawString("x", theCheck.Font, Brushes.Black, theCheck.Left * scalex + 1, theCheck.Top * scaley + 1, new StringFormat());
                }
            }

}

我将此代码用于我的打印预览，但它为

指定了错误

if (Controls[i].GetType() == this.RetirementPlanCheck.GetType())//RetirementPlanCheck

和

 if (Controls[i].GetType() == this.Wages.GetType())// wages

错误表示缺少引用，那么引用的引用类型是什么？请帮我解决这个问题。

错误味精 1.'WindowsFormsApplication1.Sinhala'不包含'Wages'的定义，并且没有扩展方法'Wages'接受类型'WindowsFormsApplication1.Sinhala'的第一个参数可以找到（你是否缺少using指令或汇编引用？） D：\ yashpppp_modi \ WindowsFormsApplication1 \ Sinhala.cs 825 51 WindowsFormsApplication1

2.'WindowsFormsApplication1.Sinhala'不包含'RetirementPlanCheck'的定义，并且没有扩展方法'RetirementPlanCheck'接受类型为'WindowsFormsApplication1.Sinhala'的第一个参数'（你是否缺少using指令或程序集）参考？）D：\ yashpppp_modi \ WindowsFormsApplication1 \ Sinhala.cs WindowsFormsApplication1

Answer 1

在C＃Corner的示例中，您引用的代码段位于类Form1的方法中。此类Form1有两个名为Wages和RetirementPlanCheck的属性，定义为

public System.Windows.Forms.TextBox Wages;
public System.Windows.Forms.CheckBox RetirementPlanCheck;

您尝试使用它的类没有这些属性，这就是编译器所抱怨的。

您是否真的尝试从您提供的链接下载完整示例？它为我构建和运行没有任何问题。或者，如果您使用提供的示例遇到此问题，您是否可能会从表单中意外删除Wages文本框和RetirementPlanCheck复选框控件？

Answer 2

您似乎没有任何名为Wages或RetirementPlanCheck的控件。

我猜这些实际上被称为其他东西，可能是txtWages和chkRetirementPlan ..

查看你的代码，我认为你可以改变你的if语句来避免这种情况：

//if (Controls[i].GetType() == this.Wages.GetType())
if (Controls[i] is TextBox)
...
//if (Controls[i].GetType() == this.RetirementPlanCheck.GetType())
if (Controls[i] is CheckBox)

如何修复此文本框打印预览？

2 个答案: