如何使这个方法工作

Question

嘿我试图创建一个类似......的方法。

    private void btnSubmit_Click(object sender, EventArgs e)
    {
        FillIn();
    }

    private void FillIn()
    {
        if (txtName.Text == "")
        {
            txtName.Text = "Bob Frank";
        }
        if (txtAddress.Text == "")
        {
            txtAddress.Text = "4111 N Pensyvania Ave.";
        }
        if (txtCity.Text == "")
        {
            txtCity.Text = "Longbeach";
        }
        if (txtState.Text == "")
        {
            txtState.Text = "CA";
        }
        if(txtZip.Text == "")
        {
            txtZip = "90210";
        }
    }

这段代码效果很好但是当我尝试像这样添加参数时..

    private void btnSubmit_Click(object sender, EventArgs e)
    {
        FillIn(txtName.Text, txtStreetAddress.Text, txtCity.Text, txtState.Text, txtZip.Text);
    }

    private void FillIn(string name, string address, string city, string state, string zip)
    {
        if (name == "")
        {
            name = "Bob Frank";
        }
        if (address == "")
        {
            address = "4111 N Pensyvania Ave.";
        }
        if (city == "")
        {
            city = "Longbeach";
        }
        if (state == "")
        {
            state = "CA";
        }
        if(zip == "")
        {
            zip = "99210";
        }
    }

它停止工作，文本框不会重新填写并输出错误，我该如何解决？

Answer 1

您需要传递实际控件。如果您尝试传递txtName.Text，它只是读取属性中的值而您无法更新它。

private void btnSubmit_Click(object sender, EventArgs e)
{
    FillIn(txtName, txtStreetAddress, txtCity, txtState, txtZip);
}

private void FillIn(TextBox name, TextBox address, TextBox city, TextBox state, TextBox zip)
{
    if (name.Text == "")
    {
        name.Text = "Bob Frank";
    }
    if (address.Text == "")
    {
        address.Text = "4111 N Pensyvania Ave.";
    }
    if (city.Text == "")
    {
        city.Text = "Longbeach";
    }
    if (state.Text == "")
    {
        state.Text = "CA";
    }
    if(zip.Text == "")
    {
        zip.Text = "99210";
    }
}