Entity Framework 设置了最大长度 超出时怎么自动截取？？急急急

Question



this.Property(p => p.Title).IsRequired().HasColumnType("varchar").HasMaxLength(256);

我设置了Title的最大长度为256，如果表单输入字符串的长度超出256，Entity Framework就直接把它抛异常了，我想让他自动截取为256长度要怎么做呢?  大哥们帮帮忙吧  谢谢！！

Answer 1

HasMaxLength限制了最大允许容量只能是256（nvarchar）个字符。因此我建议你设法用js在UI端判断输入字符长度是否超过256个。

或者在保存的时候：

xxEntityName.someProperty = xxEntityName.someProperty.ToString().SubString(0,256);

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Answer 2

我希望能够自动截取可以么？？

Answer 3

我希望能够自动截取可以么？？

恐怕不行。

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Answer 4

额，那就麻烦了   谢谢！！

Answer 5

  

你好，

你可以尝试这样的方法：

this.Property(p => (p.Name.ToString().Length > 256 ? p.Name.ToString().Substring(0, 256) : p.Name)).IsRequired().HasColumnType("varchar").HasMaxLength(256);

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