Error 1 Static member 'string.Format(string, object)' cannot be accessed with an instance reference; qualify it with a type name instead E:\VCShape\ZmCalc\ZmCalc\MitnkCalc.cs 43 13 ZmCalc============== what's the problem?
double d = 12.0025; Text = string.Format("{0:#.000}", d);
double d=12.0025; string str = string.Format("{0:0.000}", d); if (str != "12.003") { throw new Exception(); }
to zswang 如果我想要40个小数位 是不是得写成 {0:#.0000000000000000000000000000000000000000}?汗
1.可读性比连加好看 如:string str = "select * from "+ strTable +" where name="+strValue; 而用Format string.Format("select * from {0} where name='{1}'",strTable ,strValue); 在检查SQL 错误时,容易差错特别是出现"'',%"这样的符号 2.格式化的时候不需要指定是什么数据类型 int nID = 1; string str = "select * from "+ strTable +" where ID ="+nID.ToString();//nID需要转化成string string.Format("select * from {0} where ID={1}",strTable ,nID);//nID在这里不需要转换3.比C++格式化方式更灵活 当字符串出现相同的字符时,需要都列出来.如 C++ str.Format(" %0.3f ABCDEF %d %0.3f", d,A,d);//参数根据 %的顺序而定 C# string.Format(" {0} ABCDEF {1} {0}", d,A);//在{}需要指定参数的顺序
to zswang 如果我想要40个小数位 是不是得写成 {0:#.0000000000000000000000000000000000000000}?汗可以这样写: double D = Math.Round(d, 3, MidpointRounding.AwayFromZero); D.ToString();
what's the problem?
Text = string.Format("{0:#.000}", d);
string str = string.Format("{0:0.000}", d);
if (str != "12.003")
{
throw new Exception();
}
如果我想要40个小数位
是不是得写成
{0:#.0000000000000000000000000000000000000000}?汗
如:string str = "select * from "+ strTable +" where name="+strValue;
而用Format
string.Format("select * from {0} where name='{1}'",strTable ,strValue);
在检查SQL 错误时,容易差错特别是出现"'',%"这样的符号
2.格式化的时候不需要指定是什么数据类型
int nID = 1;
string str = "select * from "+ strTable +" where ID ="+nID.ToString();//nID需要转化成string
string.Format("select * from {0} where ID={1}",strTable ,nID);//nID在这里不需要转换3.比C++格式化方式更灵活
当字符串出现相同的字符时,需要都列出来.如
C++ str.Format(" %0.3f ABCDEF %d %0.3f", d,A,d);//参数根据 %的顺序而定
C# string.Format(" {0} ABCDEF {1} {0}", d,A);//在{}需要指定参数的顺序
如果我想要40个小数位
是不是得写成
{0:#.0000000000000000000000000000000000000000}?汗可以这样写:
double D = Math.Round(d, 3, MidpointRounding.AwayFromZero);
D.ToString();