[英]Count the number of TextBoxes and CheckBoxes in a form
我的要求是當用戶點擊'btnGetCount'
時,直接在表單內部使用id="form1"
計算TextBox和CheckBox的總數。 這是我嘗試過的代碼,盡管我在表單中有三個TextBoxes和兩個CheckBoxes,但它不計數任何內容,計數器仍為零。 但是,如果我刪除foreach循環並傳遞TextBox control = new TextBox();
而不是當前代碼然后它計算第一個TextBox和countTB返回值為一。
protected void btnGetCount_Click(object sender, EventArgs e)
{
Control control = new Control();
int countCB = 0;
int countTB = 0;
foreach (Control c in this.Controls)
{
if (control.GetType() == typeof(CheckBox))
{
countCB++;
}
else if (control is TextBox)
{
countTB++;
}
}
Response.Write("No of TextBoxes: " + countTB);
Response.Write("<br>");
Response.Write("No of CheckBoxes: " + countCB);
}
您必須遞歸遍歷其他控件。
<form id="form1" runat="server">
<div>
<asp:TextBox ID="txt" runat="server"></asp:TextBox>
<asp:CheckBox ID="cb" runat="server"></asp:CheckBox>
</div>
</form>
protected void Page_Load(object sender, EventArgs e)
{
var controls = form1.Controls;
var tbCount = 0;
var cbCount = 0;
CountControls(ref tbCount, controls, ref cbCount);
Response.Write(tbCount);
Response.Write(cbCount);
}
private static void CountControls(ref int tbCount, ControlCollection controls, ref int cbCount)
{
foreach (Control wc in controls)
{
if (wc is TextBox)
tbCount++;
else if (wc is CheckBox)
cbCount++;
else if(wc.Controls.Count > 0)
CountControls(ref tbCount, wc.Controls, ref cbCount);
}
}
它允許給你零,因為你計算控制控件的類型是不可用的,將你的代碼更改為:
protected void btnGetCount_Click(object sender, EventArgs e)
{
int countCB = 0;
int countTB = 0;
foreach (Control c in this.Controls)
{
if (c.GetType() == typeof(CheckBox))
{
countCB++;
}
else if (c.GetType()== typeof(TextBox))
{
countTB++;
}
}
Response.Write("No of TextBoxes: " + countTB);
Response.Write("<br>");
Response.Write("No of CheckBoxes: " + countCB);
}
我相信你必須是遞歸的, this.Controls
只會返回它的直接子this.Controls
的控件。 如果TextBox
位於其中的控件組內,則還需要查看容器控件。
請參見以下其他stackoverflow的答案: 如何獲取特定類型(按鈕/文本框)的Windows窗體表單的所有子控件?
編輯:我意識到答案是WinForms,但解決方案仍然適用。
只需對Alyafey,pcnThird和Valamas建議的代碼做一些小的改動,我就可以編寫出此代碼。
protected void btnGetCount_Click(object sender, EventArgs e)
{
int countCB = 0;
int countTB = 0;
foreach (Control c in form1.Controls) //here is the minor change
{
if (c.GetType() == typeof(CheckBox))
{
countCB++;
}
else if (c.GetType()== typeof(TextBox))
{
countTB++;
}
}
Response.Write("No of TextBoxes: " + countTB);
Response.Write("<br>");
Response.Write("No of CheckBoxes: " + countCB);
}
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