2

我有进行 REST 调用的 grails 应用程序。如果发生错误，则返回一个包含错误消息的 JSON 数组。我需要将这些字符串组合成一个字符串。但是，当我这样做时，会将双引号添加到字符串的开头和结尾。我写了一个简单的测试控制器来说明这个问题：

import net.sf.json.*
class MyController {

    def test = {

        String msg = "'fred' is not a valid LDAP distinguished name."
        JSONArray messages = new JSONArray()
        messages.add(msg)
        def renderStr = messages.join('<br/>')

        render(renderStr)
    }
}

输出如下所示：

"'fred' is not a valid LDAP distinguished name."
4

2 回答 2

3

问题是 join 函数返回 JSON-spec 字符串......根据他们的文档：http: //grails.org/doc/1.0.3/api/org/codehaus/groovy/grails/web/json /JSONArray.html

 The texts produced by the toString methods strictly conform to JSON syntax rules. The constructors are more forgiving in the texts they will accept:

    An extra , (comma) may appear just before the closing bracket.
    The null value will be inserted when there is , (comma) elision.
    Strings may be quoted with ' (single quote).
    Strings do not need to be quoted at all if they do not begin with a quote or single quote, and if they do not contain leading or trailing spaces, and if they do not contain any of these characters: { } [ ] / \ : , = ; # and if they do not look like numbers and if they are not the reserved words true, false, or null.
    Values can be separated by ; (semicolon) as well as by , (comma).
    Numbers may have the 0- (octal) or 0x- (hex) prefix.
    Comments written in the slashshlash, slashstar, and hash conventions will be ignored.

请注意，“如果字符串不以引号或单引号开头，则根本不需要引用”的规则正在发生。您的字符串以引号开头，因此如果输出时不带引号，JSON 解析器将假定该字符串以第二个单引号结尾，之后的文本将是不可解析的垃圾。

于 2012-09-15T05:03:58.507 回答
0

使用这个方便的方法

private String joinJSONArray(arr, delim = ',') {
    def result = ''

    arr.eachWithIndex { e, i ->
        result += e

        if (i != arr.size() - 1) {
            result += delim
        }
    }

    result
}

它利用eachWithIndexGroovy 不提供injectWithIndex.

于 2014-11-05T11:00:55.553 回答