为什么无法执行?新手刚学,谢谢!
string comparison;
Console.WriteLine( "Enter a number: ");
double var1 = Convert.ToDouble(Console.ReadLine());
Console.WriteLine( "Enter another number: ");
double var2 = Convert.ToDouble(Console.ReadLine());
if (var1 < var2)
comparison = "less than ";
if (var1 == var2)
comparison = "equal to ";
if (var1 > var2)
comparison = "greater than ";
Console.WriteLine( "The first number is {0} the second number. ", comparison);//怎么能有错误呢？提示说Use of unassigned local variable 'comparison '
Console.ReadKey();
[解决办法]
它不知道前面3个if已经包括了所有可能，认为还存在没有给comparison赋值的可能，因此报错
可以事先先给comparison赋一个 " "
string comparison= " ";
或者改一下判断
if (var1 < var2)
comparison = "less than ";
else if (var1 == var2)
comparison = "equal to ";
else
comparison = "greater than ";
[解决办法]
local变量要先赋值再使用
string comparison = string.Empty;//-------> 这里改成这样
Console.WriteLine( "Enter a number: ");
double var1 = Convert.ToDouble(Console.ReadLine());
Console.WriteLine( "Enter another number: ");
double var2 = Convert.ToDouble(Console.ReadLine());
if (var1 < var2)
comparison = "less than ";
if (var1 == var2)
comparison = "equal to ";
if (var1 > var2)
comparison = "greater than ";
Console.WriteLine( "The first number is {0} the second number. ", comparison);
Console.ReadKey();
[解决办法]
string comparison; -> string comparison= " ";
编译器会检查变量使用时是否有初始值,否则编译通不过.
好象回答了一个远古问题...
------解决方案--------------------
由于你的判断if语句出口不全（缺少else）,所以可能comparison没有进行初始化或赋值就是用，所以会出错
[解决办法]
结帖方法：点击帖子右上的“管理”链接，进入管理页面，在要给分的回复后的文本框中填写分数，然后输入自己的密码，点击“给分”按钮。结帖图例http://community.csdn.net/over.htm
