Cast on a "float" sequence throws InvalidCastException
2011-04-28 15:12
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原因 :The Cast method only supports reference and boxing conversions. Use Select instead:
就是说cast<>()方法只支持装箱和拆箱操作,其他强制类型转换不支持。
比如:你要完成以下代码,会抛出异常的:
而这样是可以的:
就是说cast<>()方法只支持装箱和拆箱操作,其他强制类型转换不支持。
比如:你要完成以下代码,会抛出异常的:
static void Main(string[] args) { Hashtable st = new Hashtable(); st.Add("a",12); st.Add("b",13); st.Add("c", 14); double sum = st.Values.Cast<float>().Sum(); }
而这样是可以的:
Hashtable st = new Hashtable(); st.Add("a",12f); st.Add("b",13f); st.Add("c", 14f); double sum = st.Values.Cast<float>().Sum();
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