Question

asp.net c# 输入字符串格式不正确

protected void Page_Load(object sender, EventArgs e)
{
int s;
int d;
d = int.Parse(TextBox1.Text);
s = (int)d / 10;
switch (s)
{
case 0:
case 1:
case 2:
case 3:
case 4:
case 5:
Label1.Text = "bujige"; break;
case 6:
case 7:
case 8:
Label1.Text = "hao"; break;
case 9:
case 10:
Label1.Text = "good"; break;
default: Label1.Text = "qingshuru"; break;

}

Answer 1

原因是在页面第一次载入时，TextBox1.Text的值为空，int.Parse(TextBox1.Text)会抛出异常，可以用try...catch来解决。

protected void Page_Load(object sender, EventArgs e)
{
try
{
int s;
int d;
d = int.Parse(TextBox1.Text);
s = (int)d / 10;
switch (s)
{
case 0:
case 1:
case 2:
case 3:
case 4:
case 5:
Label1.Text = "bujige"; break;
case 6:
case 7:
case 8:
Label1.Text = "hao"; break;
case 9:
case 10:
Label1.Text = "good"; break;
default: Label1.Text = "qingshuru"; break;
}
}
catch
{
}
}

Answer 2

是不是TextBox1.Text 如果输入的不是数字,就数变成 请输入啊????

你做异常处理就行了!~
try
{
d = int.Parse(TextBox1.Text);
s = (int)d / 10;
switch (s)
{
case 0:
case 1:
case 2:
case 3:
case 4:
case 5:
Label1.Text = "bujige"; break;
case 6:
case 7:
case 8:
Label1.Text = "hao"; break;
case 9:
case 10:
Label1.Text = "good"; break;
default: Label1.Text = "qingshuru"; break;
}
}
catch(Exception e)
{
Label1.Text = "请正确输入!";
}

Answer 3

如果TextBox1.Text的值不能转为int型的当然要抛出异常
比如"check"就无法转为int而"12"就可以
你可以使用int,tryParse方法
第一个参数写TextBox1.text,第二个参数是输出参数out d
方法返回bool型 true为转型成功 false为失败
成功d就是TextBox1.text转化的值

Answer 4

用try catch捕获下错误